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<div class="section" id="lexical-analysis">
<span id="lexical"></span><h1>2. Lexical analysis<a class="headerlink" href="#lexical-analysis" title="Permalink to this headline">¶</a></h1>
<p id="index-866">A Python program is read by a <em>parser</em>. Input to the parser is a stream of
<em>tokens</em>, generated by the <em>lexical analyzer</em>. This chapter describes how the
lexical analyzer breaks a file into tokens.</p>
<p>Python reads program text as Unicode code points; the encoding of a source file
can be given by an encoding declaration and defaults to UTF-8, see <span class="target" id="index-867"></span><a class="reference external" href="http://www.python.org/dev/peps/pep-3120"><strong>PEP 3120</strong></a>
for details. If the source file cannot be decoded, a <a title="exceptions.SyntaxError" class="reference external" href="../library/exceptions.html#exceptions.SyntaxError"><tt class="xref docutils literal"><span class="pre">SyntaxError</span></tt></a> is
raised.</p>
<div class="section" id="line-structure">
<span id="id1"></span><h2>2.1. Line structure<a class="headerlink" href="#line-structure" title="Permalink to this headline">¶</a></h2>
<p id="index-868">A Python program is divided into a number of <em>logical lines</em>.</p>
<div class="section" id="logical-lines">
<span id="id2"></span><h3>2.1.1. Logical lines<a class="headerlink" href="#logical-lines" title="Permalink to this headline">¶</a></h3>
<p id="index-869">The end of a logical line is represented by the token NEWLINE. Statements
cannot cross logical line boundaries except where NEWLINE is allowed by the
syntax (e.g., between statements in compound statements). A logical line is
constructed from one or more <em>physical lines</em> by following the explicit or
implicit <em>line joining</em> rules.</p>
</div>
<div class="section" id="physical-lines">
<span id="id3"></span><h3>2.1.2. Physical lines<a class="headerlink" href="#physical-lines" title="Permalink to this headline">¶</a></h3>
<p>A physical line is a sequence of characters terminated by an end-of-line
sequence. In source files, any of the standard platform line termination
sequences can be used - the Unix form using ASCII LF (linefeed), the Windows
form using the ASCII sequence CR LF (return followed by linefeed), or the old
Macintosh form using the ASCII CR (return) character. All of these forms can be
used equally, regardless of platform.</p>
<p>When embedding Python, source code strings should be passed to Python APIs using
the standard C conventions for newline characters (the <tt class="docutils literal"><span class="pre">\n</span></tt> character,
representing ASCII LF, is the line terminator).</p>
</div>
<div class="section" id="comments">
<span id="id4"></span><h3>2.1.3. Comments<a class="headerlink" href="#comments" title="Permalink to this headline">¶</a></h3>
<p id="index-870">A comment starts with a hash character (<tt class="docutils literal"><span class="pre">#</span></tt>) that is not part of a string
literal, and ends at the end of the physical line. A comment signifies the end
of the logical line unless the implicit line joining rules are invoked. Comments
are ignored by the syntax; they are not tokens.</p>
</div>
<div class="section" id="encoding-declarations">
<span id="encodings"></span><h3>2.1.4. Encoding declarations<a class="headerlink" href="#encoding-declarations" title="Permalink to this headline">¶</a></h3>
<p id="index-871">If a comment in the first or second line of the Python script matches the
regular expression <tt class="docutils literal"><span class="pre">coding[=:]\s*([-\w.]+)</span></tt>, this comment is processed as an
encoding declaration; the first group of this expression names the encoding of
the source code file. The recommended forms of this expression are</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="c"># -*- coding: <encoding-name> -*-</span>
</pre></div>
</div>
<p>which is recognized also by GNU Emacs, and</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="c"># vim:fileencoding=<encoding-name></span>
</pre></div>
</div>
<p>which is recognized by Bram Moolenaar’s VIM.</p>
<p>If no encoding declaration is found, the default encoding is UTF-8. In
addition, if the first bytes of the file are the UTF-8 byte-order mark
(<tt class="docutils literal"><span class="pre">b'\xef\xbb\xbf'</span></tt>), the declared file encoding is UTF-8 (this is supported,
among others, by Microsoft’s <strong>notepad</strong>).</p>
<p>If an encoding is declared, the encoding name must be recognized by Python. The
encoding is used for all lexical analysis, including string literals, comments
and identifiers. The encoding declaration must appear on a line of its own.</p>
</div>
<div class="section" id="explicit-line-joining">
<span id="explicit-joining"></span><h3>2.1.5. Explicit line joining<a class="headerlink" href="#explicit-line-joining" title="Permalink to this headline">¶</a></h3>
<p id="index-872">Two or more physical lines may be joined into logical lines using backslash
characters (<tt class="docutils literal"><span class="pre">\</span></tt>), as follows: when a physical line ends in a backslash that is
not part of a string literal or comment, it is joined with the following forming
a single logical line, deleting the backslash and the following end-of-line
character. For example:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="k">if</span> <span class="mi">1900</span> <span class="o"><</span> <span class="n">year</span> <span class="o"><</span> <span class="mi">2100</span> <span class="ow">and</span> <span class="mi">1</span> <span class="o"><=</span> <span class="n">month</span> <span class="o"><=</span> <span class="mi">12</span> \
<span class="ow">and</span> <span class="mi">1</span> <span class="o"><=</span> <span class="n">day</span> <span class="o"><=</span> <span class="mi">31</span> <span class="ow">and</span> <span class="mi">0</span> <span class="o"><=</span> <span class="n">hour</span> <span class="o"><</span> <span class="mi">24</span> \
<span class="ow">and</span> <span class="mi">0</span> <span class="o"><=</span> <span class="n">minute</span> <span class="o"><</span> <span class="mi">60</span> <span class="ow">and</span> <span class="mi">0</span> <span class="o"><=</span> <span class="n">second</span> <span class="o"><</span> <span class="mi">60</span><span class="p">:</span> <span class="c"># Looks like a valid date</span>
<span class="k">return</span> <span class="mi">1</span>
</pre></div>
</div>
<p>A line ending in a backslash cannot carry a comment. A backslash does not
continue a comment. A backslash does not continue a token except for string
literals (i.e., tokens other than string literals cannot be split across
physical lines using a backslash). A backslash is illegal elsewhere on a line
outside a string literal.</p>
</div>
<div class="section" id="implicit-line-joining">
<span id="implicit-joining"></span><h3>2.1.6. Implicit line joining<a class="headerlink" href="#implicit-line-joining" title="Permalink to this headline">¶</a></h3>
<p>Expressions in parentheses, square brackets or curly braces can be split over
more than one physical line without using backslashes. For example:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="n">month_names</span> <span class="o">=</span> <span class="p">[</span><span class="s">'Januari'</span><span class="p">,</span> <span class="s">'Februari'</span><span class="p">,</span> <span class="s">'Maart'</span><span class="p">,</span> <span class="c"># These are the</span>
<span class="s">'April'</span><span class="p">,</span> <span class="s">'Mei'</span><span class="p">,</span> <span class="s">'Juni'</span><span class="p">,</span> <span class="c"># Dutch names</span>
<span class="s">'Juli'</span><span class="p">,</span> <span class="s">'Augustus'</span><span class="p">,</span> <span class="s">'September'</span><span class="p">,</span> <span class="c"># for the months</span>
<span class="s">'Oktober'</span><span class="p">,</span> <span class="s">'November'</span><span class="p">,</span> <span class="s">'December'</span><span class="p">]</span> <span class="c"># of the year</span>
</pre></div>
</div>
<p>Implicitly continued lines can carry comments. The indentation of the
continuation lines is not important. Blank continuation lines are allowed.
There is no NEWLINE token between implicit continuation lines. Implicitly
continued lines can also occur within triple-quoted strings (see below); in that
case they cannot carry comments.</p>
</div>
<div class="section" id="blank-lines">
<span id="id5"></span><h3>2.1.7. Blank lines<a class="headerlink" href="#blank-lines" title="Permalink to this headline">¶</a></h3>
<p id="index-873">A logical line that contains only spaces, tabs, formfeeds and possibly a
comment, is ignored (i.e., no NEWLINE token is generated). During interactive
input of statements, handling of a blank line may differ depending on the
implementation of the read-eval-print loop. In the standard interactive
interpreter, an entirely blank logical line (i.e. one containing not even
whitespace or a comment) terminates a multi-line statement.</p>
</div>
<div class="section" id="indentation">
<span id="id6"></span><h3>2.1.8. Indentation<a class="headerlink" href="#indentation" title="Permalink to this headline">¶</a></h3>
<p id="index-874">Leading whitespace (spaces and tabs) at the beginning of a logical line is used
to compute the indentation level of the line, which in turn is used to determine
the grouping of statements.</p>
<p>Tabs are replaced (from left to right) by one to eight spaces such that the
total number of characters up to and including the replacement is a multiple of
eight (this is intended to be the same rule as used by Unix). The total number
of spaces preceding the first non-blank character then determines the line’s
indentation. Indentation cannot be split over multiple physical lines using
backslashes; the whitespace up to the first backslash determines the
indentation.</p>
<p>Indentation is rejected as inconsistent if a source file mixes tabs and spaces
in a way that makes the meaning dependent on the worth of a tab in spaces; a
<tt class="xref docutils literal"><span class="pre">TabError</span></tt> is raised in that case.</p>
<p><strong>Cross-platform compatibility note:</strong> because of the nature of text editors on
non-UNIX platforms, it is unwise to use a mixture of spaces and tabs for the
indentation in a single source file. It should also be noted that different
platforms may explicitly limit the maximum indentation level.</p>
<p>A formfeed character may be present at the start of the line; it will be ignored
for the indentation calculations above. Formfeed characters occurring elsewhere
in the leading whitespace have an undefined effect (for instance, they may reset
the space count to zero).</p>
<p id="index-875">The indentation levels of consecutive lines are used to generate INDENT and
DEDENT tokens, using a stack, as follows.</p>
<p>Before the first line of the file is read, a single zero is pushed on the stack;
this will never be popped off again. The numbers pushed on the stack will
always be strictly increasing from bottom to top. At the beginning of each
logical line, the line’s indentation level is compared to the top of the stack.
If it is equal, nothing happens. If it is larger, it is pushed on the stack, and
one INDENT token is generated. If it is smaller, it <em>must</em> be one of the
numbers occurring on the stack; all numbers on the stack that are larger are
popped off, and for each number popped off a DEDENT token is generated. At the
end of the file, a DEDENT token is generated for each number remaining on the
stack that is larger than zero.</p>
<p>Here is an example of a correctly (though confusingly) indented piece of Python
code:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="k">def</span> <span class="nf">perm</span><span class="p">(</span><span class="n">l</span><span class="p">):</span>
<span class="c"># Compute the list of all permutations of l</span>
<span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">l</span><span class="p">)</span> <span class="o"><=</span> <span class="mi">1</span><span class="p">:</span>
<span class="k">return</span> <span class="p">[</span><span class="n">l</span><span class="p">]</span>
<span class="n">r</span> <span class="o">=</span> <span class="p">[]</span>
<span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="n">l</span><span class="p">)):</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">l</span><span class="p">[:</span><span class="n">i</span><span class="p">]</span> <span class="o">+</span> <span class="n">l</span><span class="p">[</span><span class="n">i</span><span class="o">+</span><span class="mi">1</span><span class="p">:]</span>
<span class="n">p</span> <span class="o">=</span> <span class="n">perm</span><span class="p">(</span><span class="n">s</span><span class="p">)</span>
<span class="k">for</span> <span class="n">x</span> <span class="ow">in</span> <span class="n">p</span><span class="p">:</span>
<span class="n">r</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">l</span><span class="p">[</span><span class="n">i</span><span class="p">:</span><span class="n">i</span><span class="o">+</span><span class="mi">1</span><span class="p">]</span> <span class="o">+</span> <span class="n">x</span><span class="p">)</span>
<span class="k">return</span> <span class="n">r</span>
</pre></div>
</div>
<p>The following example shows various indentation errors:</p>
<div class="highlight-python3"><div class="highlight"><pre> <span class="k">def</span> <span class="nf">perm</span><span class="p">(</span><span class="n">l</span><span class="p">):</span> <span class="c"># error: first line indented</span>
<span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="n">l</span><span class="p">)):</span> <span class="c"># error: not indented</span>
<span class="n">s</span> <span class="o">=</span> <span class="n">l</span><span class="p">[:</span><span class="n">i</span><span class="p">]</span> <span class="o">+</span> <span class="n">l</span><span class="p">[</span><span class="n">i</span><span class="o">+</span><span class="mi">1</span><span class="p">:]</span>
<span class="n">p</span> <span class="o">=</span> <span class="n">perm</span><span class="p">(</span><span class="n">l</span><span class="p">[:</span><span class="n">i</span><span class="p">]</span> <span class="o">+</span> <span class="n">l</span><span class="p">[</span><span class="n">i</span><span class="o">+</span><span class="mi">1</span><span class="p">:])</span> <span class="c"># error: unexpected indent</span>
<span class="k">for</span> <span class="n">x</span> <span class="ow">in</span> <span class="n">p</span><span class="p">:</span>
<span class="n">r</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">l</span><span class="p">[</span><span class="n">i</span><span class="p">:</span><span class="n">i</span><span class="o">+</span><span class="mi">1</span><span class="p">]</span> <span class="o">+</span> <span class="n">x</span><span class="p">)</span>
<span class="k">return</span> <span class="n">r</span> <span class="c"># error: inconsistent dedent</span>
</pre></div>
</div>
<p>(Actually, the first three errors are detected by the parser; only the last
error is found by the lexical analyzer — the indentation of <tt class="docutils literal"><span class="pre">return</span> <span class="pre">r</span></tt> does
not match a level popped off the stack.)</p>
</div>
<div class="section" id="whitespace-between-tokens">
<span id="whitespace"></span><h3>2.1.9. Whitespace between tokens<a class="headerlink" href="#whitespace-between-tokens" title="Permalink to this headline">¶</a></h3>
<p>Except at the beginning of a logical line or in string literals, the whitespace
characters space, tab and formfeed can be used interchangeably to separate
tokens. Whitespace is needed between two tokens only if their concatenation
could otherwise be interpreted as a different token (e.g., ab is one token, but
a b is two tokens).</p>
</div>
</div>
<div class="section" id="other-tokens">
<span id="id7"></span><h2>2.2. Other tokens<a class="headerlink" href="#other-tokens" title="Permalink to this headline">¶</a></h2>
<p>Besides NEWLINE, INDENT and DEDENT, the following categories of tokens exist:
<em>identifiers</em>, <em>keywords</em>, <em>literals</em>, <em>operators</em>, and <em>delimiters</em>. Whitespace
characters (other than line terminators, discussed earlier) are not tokens, but
serve to delimit tokens. Where ambiguity exists, a token comprises the longest
possible string that forms a legal token, when read from left to right.</p>
</div>
<div class="section" id="identifiers">
<span id="identifiers-and-keywords"></span><h2>2.3. Identifiers and keywords<a class="headerlink" href="#identifiers" title="Permalink to this headline">¶</a></h2>
<p id="index-876">Identifiers (also referred to as <em>names</em>) are described by the following lexical
definitions.</p>
<p>The syntax of identifiers in Python is based on the Unicode standard annex
UAX-31, with elaboration and changes as defined below; see also <span class="target" id="index-877"></span><a class="reference external" href="http://www.python.org/dev/peps/pep-3131"><strong>PEP 3131</strong></a> for
further details.</p>
<p>Within the ASCII range (U+0001..U+007F), the valid characters for identifiers
are the same as in Python 2.x: the uppercase and lowercase letters <tt class="docutils literal"><span class="pre">A</span></tt> through
<tt class="docutils literal"><span class="pre">Z</span></tt>, the underscore <tt class="docutils literal"><span class="pre">_</span></tt> and, except for the first character, the digits
<tt class="docutils literal"><span class="pre">0</span></tt> through <tt class="docutils literal"><span class="pre">9</span></tt>.</p>
<p>Python 3.0 introduces additional characters from outside the ASCII range (see
<span class="target" id="index-878"></span><a class="reference external" href="http://www.python.org/dev/peps/pep-3131"><strong>PEP 3131</strong></a>). For these characters, the classification uses the version of the
Unicode Character Database as included in the <a title="Access the Unicode Database." class="reference external" href="../library/unicodedata.html#module-unicodedata"><tt class="xref docutils literal"><span class="pre">unicodedata</span></tt></a> module.</p>
<p>Identifiers are unlimited in length. Case is significant.</p>
<pre>
<strong id="grammar-token-identifier">identifier </strong> ::= <a class="reference internal" href="#grammar-token-id_start"><tt class="xref docutils literal"><span class="pre">id_start</span></tt></a> <a class="reference internal" href="#grammar-token-id_continue"><tt class="xref docutils literal"><span class="pre">id_continue</span></tt></a>*
<strong id="grammar-token-id_start">id_start </strong> ::= <all characters in general categories Lu, Ll, Lt, Lm, Lo, Nl, the underscore, and characters with the Other_ID_Start property>
<strong id="grammar-token-id_continue">id_continue</strong> ::= <all characters in <a class="reference internal" href="#grammar-token-id_start"><tt class="xref docutils literal"><span class="pre">id_start</span></tt></a>, plus characters in the categories Mn, Mc, Nd, Pc and others with the Other_ID_Continue property>
</pre>
<p>The Unicode category codes mentioned above stand for:</p>
<ul class="simple">
<li><em>Lu</em> - uppercase letters</li>
<li><em>Ll</em> - lowercase letters</li>
<li><em>Lt</em> - titlecase letters</li>
<li><em>Lm</em> - modifier letters</li>
<li><em>Lo</em> - other letters</li>
<li><em>Nl</em> - letter numbers</li>
<li><em>Mn</em> - nonspacing marks</li>
<li><em>Mc</em> - spacing combining marks</li>
<li><em>Nd</em> - decimal numbers</li>
<li><em>Pc</em> - connector punctuations</li>
</ul>
<p>All identifiers are converted into the normal form NFC while parsing; comparison
of identifiers is based on NFC.</p>
<p>A non-normative HTML file listing all valid identifier characters for Unicode
4.1 can be found at
<a class="reference external" href="http://www.dcl.hpi.uni-potsdam.de/home/loewis/table-3131.html">http://www.dcl.hpi.uni-potsdam.de/home/loewis/table-3131.html</a>.</p>
<div class="section" id="keywords">
<span id="id8"></span><h3>2.3.1. Keywords<a class="headerlink" href="#keywords" title="Permalink to this headline">¶</a></h3>
<p id="index-879">The following identifiers are used as reserved words, or <em>keywords</em> of the
language, and cannot be used as ordinary identifiers. They must be spelled
exactly as written here:</p>
<div class="highlight-text"><div class="highlight"><pre>False class finally is return
None continue for lambda try
True def from nonlocal while
and del global not with
as elif if or yield
assert else import pass
break except in raise
</pre></div>
</div>
</div>
<div class="section" id="reserved-classes-of-identifiers">
<span id="id-classes"></span><h3>2.3.2. Reserved classes of identifiers<a class="headerlink" href="#reserved-classes-of-identifiers" title="Permalink to this headline">¶</a></h3>
<p>Certain classes of identifiers (besides keywords) have special meanings. These
classes are identified by the patterns of leading and trailing underscore
characters:</p>
<dl class="docutils">
<dt><tt class="docutils literal"><span class="pre">_*</span></tt></dt>
<dd><p class="first">Not imported by <tt class="docutils literal"><span class="pre">from</span> <span class="pre">module</span> <span class="pre">import</span> <span class="pre">*</span></tt>. The special identifier <tt class="docutils literal"><span class="pre">_</span></tt> is used
in the interactive interpreter to store the result of the last evaluation; it is
stored in the <a title="The module that provides the built-in namespace." class="reference external" href="../library/builtins.html#module-builtins"><tt class="xref docutils literal"><span class="pre">builtins</span></tt></a> module. When not in interactive mode, <tt class="docutils literal"><span class="pre">_</span></tt>
has no special meaning and is not defined. See section <a class="reference external" href="simple_stmts.html#import"><em>The import statement</em></a>.</p>
<div class="last admonition note">
<p class="first admonition-title">Note</p>
<p class="last">The name <tt class="docutils literal"><span class="pre">_</span></tt> is often used in conjunction with internationalization;
refer to the documentation for the <a title="Multilingual internationalization services." class="reference external" href="../library/gettext.html#module-gettext"><tt class="xref docutils literal"><span class="pre">gettext</span></tt></a> module for more
information on this convention.</p>
</div>
</dd>
<dt><tt class="docutils literal"><span class="pre">__*__</span></tt></dt>
<dd>System-defined names. These names are defined by the interpreter and its
implementation (including the standard library); applications should not expect
to define additional names using this convention. The set of names of this
class defined by Python may be extended in future versions. See section
<a class="reference external" href="datamodel.html#specialnames"><em>Special method names</em></a>.</dd>
<dt><tt class="docutils literal"><span class="pre">__*</span></tt></dt>
<dd>Class-private names. Names in this category, when used within the context of a
class definition, are re-written to use a mangled form to help avoid name
clashes between “private” attributes of base and derived classes. See section
<a class="reference external" href="expressions.html#atom-identifiers"><em>Identifiers (Names)</em></a>.</dd>
</dl>
</div>
</div>
<div class="section" id="literals">
<span id="id9"></span><h2>2.4. Literals<a class="headerlink" href="#literals" title="Permalink to this headline">¶</a></h2>
<p id="index-880">Literals are notations for constant values of some built-in types.</p>
<div class="section" id="string-and-bytes-literals">
<span id="strings"></span><h3>2.4.1. String and Bytes literals<a class="headerlink" href="#string-and-bytes-literals" title="Permalink to this headline">¶</a></h3>
<p id="index-881">String literals are described by the following lexical definitions:</p>
<pre>
<strong id="grammar-token-stringliteral">stringliteral </strong> ::= [<a class="reference internal" href="#grammar-token-stringprefix"><tt class="xref docutils literal"><span class="pre">stringprefix</span></tt></a>](<a class="reference internal" href="#grammar-token-shortstring"><tt class="xref docutils literal"><span class="pre">shortstring</span></tt></a> | <a class="reference internal" href="#grammar-token-longstring"><tt class="xref docutils literal"><span class="pre">longstring</span></tt></a>)
<strong id="grammar-token-stringprefix">stringprefix </strong> ::= "r" | "R"
<strong id="grammar-token-shortstring">shortstring </strong> ::= "'" <a class="reference internal" href="#grammar-token-shortstringitem"><tt class="xref docutils literal"><span class="pre">shortstringitem</span></tt></a>* "'" | '"' <a class="reference internal" href="#grammar-token-shortstringitem"><tt class="xref docutils literal"><span class="pre">shortstringitem</span></tt></a>* '"'
<strong id="grammar-token-longstring">longstring </strong> ::= "'''" <a class="reference internal" href="#grammar-token-longstringitem"><tt class="xref docutils literal"><span class="pre">longstringitem</span></tt></a>* "'''" | '"""' <a class="reference internal" href="#grammar-token-longstringitem"><tt class="xref docutils literal"><span class="pre">longstringitem</span></tt></a>* '"""'
<strong id="grammar-token-shortstringitem">shortstringitem</strong> ::= <a class="reference internal" href="#grammar-token-shortstringchar"><tt class="xref docutils literal"><span class="pre">shortstringchar</span></tt></a> | <a class="reference internal" href="#grammar-token-stringescapeseq"><tt class="xref docutils literal"><span class="pre">stringescapeseq</span></tt></a>
<strong id="grammar-token-longstringitem">longstringitem </strong> ::= <a class="reference internal" href="#grammar-token-longstringchar"><tt class="xref docutils literal"><span class="pre">longstringchar</span></tt></a> | <a class="reference internal" href="#grammar-token-stringescapeseq"><tt class="xref docutils literal"><span class="pre">stringescapeseq</span></tt></a>
<strong id="grammar-token-shortstringchar">shortstringchar</strong> ::= <any source character except "\" or newline or the quote>
<strong id="grammar-token-longstringchar">longstringchar </strong> ::= <any source character except "\">
<strong id="grammar-token-stringescapeseq">stringescapeseq</strong> ::= "\" <any source character>
</pre>
<pre>
<strong id="grammar-token-bytesliteral">bytesliteral </strong> ::= <a class="reference internal" href="#grammar-token-bytesprefix"><tt class="xref docutils literal"><span class="pre">bytesprefix</span></tt></a>(<a class="reference internal" href="#grammar-token-shortbytes"><tt class="xref docutils literal"><span class="pre">shortbytes</span></tt></a> | <a class="reference internal" href="#grammar-token-longbytes"><tt class="xref docutils literal"><span class="pre">longbytes</span></tt></a>)
<strong id="grammar-token-bytesprefix">bytesprefix </strong> ::= "b" | "B"
<strong id="grammar-token-shortbytes">shortbytes </strong> ::= "'" <a class="reference internal" href="#grammar-token-shortbytesitem"><tt class="xref docutils literal"><span class="pre">shortbytesitem</span></tt></a>* "'" | '"' <a class="reference internal" href="#grammar-token-shortbytesitem"><tt class="xref docutils literal"><span class="pre">shortbytesitem</span></tt></a>* '"'
<strong id="grammar-token-longbytes">longbytes </strong> ::= "'''" <a class="reference internal" href="#grammar-token-longbytesitem"><tt class="xref docutils literal"><span class="pre">longbytesitem</span></tt></a>* "'''" | '"""' <a class="reference internal" href="#grammar-token-longbytesitem"><tt class="xref docutils literal"><span class="pre">longbytesitem</span></tt></a>* '"""'
<strong id="grammar-token-shortbytesitem">shortbytesitem</strong> ::= <a class="reference internal" href="#grammar-token-shortbyteschar"><tt class="xref docutils literal"><span class="pre">shortbyteschar</span></tt></a> | <a class="reference internal" href="#grammar-token-bytesescapeseq"><tt class="xref docutils literal"><span class="pre">bytesescapeseq</span></tt></a>
<strong id="grammar-token-longbytesitem">longbytesitem </strong> ::= <a class="reference internal" href="#grammar-token-longbyteschar"><tt class="xref docutils literal"><span class="pre">longbyteschar</span></tt></a> | <a class="reference internal" href="#grammar-token-bytesescapeseq"><tt class="xref docutils literal"><span class="pre">bytesescapeseq</span></tt></a>
<strong id="grammar-token-shortbyteschar">shortbyteschar</strong> ::= <any ASCII character except "\" or newline or the quote>
<strong id="grammar-token-longbyteschar">longbyteschar </strong> ::= <any ASCII character except "\">
<strong id="grammar-token-bytesescapeseq">bytesescapeseq</strong> ::= "\" <any ASCII character>
</pre>
<p>One syntactic restriction not indicated by these productions is that whitespace
is not allowed between the <a class="reference internal" href="#grammar-token-stringprefix"><strong class="xref">stringprefix</strong></a> or <a class="reference internal" href="#grammar-token-bytesprefix"><strong class="xref">bytesprefix</strong></a> and the
rest of the literal. The source character set is defined by the encoding
declaration; it is UTF-8 if no encoding declaration is given in the source file;
see section <a class="reference internal" href="#encodings"><em>Encoding declarations</em></a>.</p>
<p id="index-882">In plain English: Both types of literals can be enclosed in matching single quotes
(<tt class="docutils literal"><span class="pre">'</span></tt>) or double quotes (<tt class="docutils literal"><span class="pre">"</span></tt>). They can also be enclosed in matching groups
of three single or double quotes (these are generally referred to as
<em>triple-quoted strings</em>). The backslash (<tt class="docutils literal"><span class="pre">\</span></tt>) character is used to escape
characters that otherwise have a special meaning, such as newline, backslash
itself, or the quote character.</p>
<p>String literals may optionally be prefixed with a letter <tt class="docutils literal"><span class="pre">'r'</span></tt> or <tt class="docutils literal"><span class="pre">'R'</span></tt>;
such strings are called <em>raw strings</em> and treat backslashes as literal
characters. As a result, <tt class="docutils literal"><span class="pre">'\U'</span></tt> and <tt class="docutils literal"><span class="pre">'\u'</span></tt> escapes in raw strings are not
treated specially.</p>
<p>Bytes literals are always prefixed with <tt class="docutils literal"><span class="pre">'b'</span></tt> or <tt class="docutils literal"><span class="pre">'B'</span></tt>; they produce an
instance of the <a title="bytes" class="reference external" href="../library/functions.html#bytes"><tt class="xref docutils literal"><span class="pre">bytes</span></tt></a> type instead of the <a title="str" class="reference external" href="../library/functions.html#str"><tt class="xref docutils literal"><span class="pre">str</span></tt></a> type. They
may only contain ASCII characters; bytes with a numeric value of 128 or greater
must be expressed with escapes.</p>
<p>In triple-quoted strings, unescaped newlines and quotes are allowed (and are
retained), except that three unescaped quotes in a row terminate the string. (A
“quote” is the character used to open the string, i.e. either <tt class="docutils literal"><span class="pre">'</span></tt> or <tt class="docutils literal"><span class="pre">"</span></tt>.)</p>
<p id="index-883">Unless an <tt class="docutils literal"><span class="pre">'r'</span></tt> or <tt class="docutils literal"><span class="pre">'R'</span></tt> prefix is present, escape sequences in strings are
interpreted according to rules similar to those used by Standard C. The
recognized escape sequences are:</p>
<table border="1" class="docutils">
<colgroup>
<col width="30%" />
<col width="58%" />
<col width="12%" />
</colgroup>
<thead valign="bottom">
<tr><th class="head">Escape Sequence</th>
<th class="head">Meaning</th>
<th class="head">Notes</th>
</tr>
</thead>
<tbody valign="top">
<tr><td><tt class="docutils literal"><span class="pre">\newline</span></tt></td>
<td>Backslash and newline ignored</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\\</span></tt></td>
<td>Backslash (<tt class="docutils literal"><span class="pre">\</span></tt>)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\'</span></tt></td>
<td>Single quote (<tt class="docutils literal"><span class="pre">'</span></tt>)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\"</span></tt></td>
<td>Double quote (<tt class="docutils literal"><span class="pre">"</span></tt>)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\a</span></tt></td>
<td>ASCII Bell (BEL)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\b</span></tt></td>
<td>ASCII Backspace (BS)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\f</span></tt></td>
<td>ASCII Formfeed (FF)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\n</span></tt></td>
<td>ASCII Linefeed (LF)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\r</span></tt></td>
<td>ASCII Carriage Return (CR)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\t</span></tt></td>
<td>ASCII Horizontal Tab (TAB)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\v</span></tt></td>
<td>ASCII Vertical Tab (VT)</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\ooo</span></tt></td>
<td>Character with octal value
<em>ooo</em></td>
<td>(1,3)</td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\xhh</span></tt></td>
<td>Character with hex value <em>hh</em></td>
<td>(2,3)</td>
</tr>
</tbody>
</table>
<p>Escape sequences only recognized in string literals are:</p>
<table border="1" class="docutils">
<colgroup>
<col width="30%" />
<col width="58%" />
<col width="12%" />
</colgroup>
<thead valign="bottom">
<tr><th class="head">Escape Sequence</th>
<th class="head">Meaning</th>
<th class="head">Notes</th>
</tr>
</thead>
<tbody valign="top">
<tr><td><tt class="docutils literal"><span class="pre">\N{name}</span></tt></td>
<td>Character named <em>name</em> in the
Unicode database</td>
<td> </td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\uxxxx</span></tt></td>
<td>Character with 16-bit hex value
<em>xxxx</em></td>
<td>(4)</td>
</tr>
<tr><td><tt class="docutils literal"><span class="pre">\Uxxxxxxxx</span></tt></td>
<td>Character with 32-bit hex value
<em>xxxxxxxx</em></td>
<td>(5)</td>
</tr>
</tbody>
</table>
<p>Notes:</p>
<ol class="arabic simple">
<li>As in Standard C, up to three octal digits are accepted.</li>
<li>Unlike in Standard C, at most two hex digits are accepted.</li>
<li>In a bytes literal, hexadecimal and octal escapes denote the byte with the
given value. In a string literal, these escapes denote a Unicode character
with the given value.</li>
<li>Individual code units which form parts of a surrogate pair can be encoded using
this escape sequence. Unlike in Standard C, exactly two hex digits are required.</li>
<li>Any Unicode character can be encoded this way, but characters outside the Basic
Multilingual Plane (BMP) will be encoded using a surrogate pair if Python is
compiled to use 16-bit code units (the default). Individual code units which
form parts of a surrogate pair can be encoded using this escape sequence.</li>
</ol>
<p id="index-884">Unlike Standard C, all unrecognized escape sequences are left in the string
unchanged, i.e., <em>the backslash is left in the string</em>. (This behavior is
useful when debugging: if an escape sequence is mistyped, the resulting output
is more easily recognized as broken.) It is also important to note that the
escape sequences only recognized in string literals fall into the category of
unrecognized escapes for bytes literals.</p>
<p>Even in a raw string, string quotes can be escaped with a backslash, but the
backslash remains in the string; for example, <tt class="docutils literal"><span class="pre">r"\""</span></tt> is a valid string
literal consisting of two characters: a backslash and a double quote; <tt class="docutils literal"><span class="pre">r"\"</span></tt>
is not a valid string literal (even a raw string cannot end in an odd number of
backslashes). Specifically, <em>a raw string cannot end in a single backslash</em>
(since the backslash would escape the following quote character). Note also
that a single backslash followed by a newline is interpreted as those two
characters as part of the string, <em>not</em> as a line continuation.</p>
</div>
<div class="section" id="string-literal-concatenation">
<span id="string-catenation"></span><h3>2.4.2. String literal concatenation<a class="headerlink" href="#string-literal-concatenation" title="Permalink to this headline">¶</a></h3>
<p>Multiple adjacent string literals (delimited by whitespace), possibly using
different quoting conventions, are allowed, and their meaning is the same as
their concatenation. Thus, <tt class="docutils literal"><span class="pre">"hello"</span> <span class="pre">'world'</span></tt> is equivalent to
<tt class="docutils literal"><span class="pre">"helloworld"</span></tt>. This feature can be used to reduce the number of backslashes
needed, to split long strings conveniently across long lines, or even to add
comments to parts of strings, for example:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="n">re</span><span class="o">.</span><span class="n">compile</span><span class="p">(</span><span class="s">"[A-Za-z_]"</span> <span class="c"># letter or underscore</span>
<span class="s">"[A-Za-z0-9_]*"</span> <span class="c"># letter, digit or underscore</span>
<span class="p">)</span>
</pre></div>
</div>
<p>Note that this feature is defined at the syntactical level, but implemented at
compile time. The ‘+’ operator must be used to concatenate string expressions
at run time. Also note that literal concatenation can use different quoting
styles for each component (even mixing raw strings and triple quoted strings).</p>
</div>
<div class="section" id="numeric-literals">
<span id="numbers"></span><h3>2.4.3. Numeric literals<a class="headerlink" href="#numeric-literals" title="Permalink to this headline">¶</a></h3>
<p id="index-885">There are three types of numeric literals: integers, floating point numbers, and
imaginary numbers. There are no complex literals (complex numbers can be formed
by adding a real number and an imaginary number).</p>
<p>Note that numeric literals do not include a sign; a phrase like <tt class="docutils literal"><span class="pre">-1</span></tt> is
actually an expression composed of the unary operator ‘<tt class="docutils literal"><span class="pre">-</span></tt>‘ and the literal
<tt class="docutils literal"><span class="pre">1</span></tt>.</p>
</div>
<div class="section" id="integer-literals">
<span id="integers"></span><h3>2.4.4. Integer literals<a class="headerlink" href="#integer-literals" title="Permalink to this headline">¶</a></h3>
<p>Integer literals are described by the following lexical definitions:</p>
<pre>
<strong id="grammar-token-integer">integer </strong> ::= <a class="reference internal" href="#grammar-token-decimalinteger"><tt class="xref docutils literal"><span class="pre">decimalinteger</span></tt></a> | <a class="reference internal" href="#grammar-token-octinteger"><tt class="xref docutils literal"><span class="pre">octinteger</span></tt></a> | <a class="reference internal" href="#grammar-token-hexinteger"><tt class="xref docutils literal"><span class="pre">hexinteger</span></tt></a> | <a class="reference internal" href="#grammar-token-bininteger"><tt class="xref docutils literal"><span class="pre">bininteger</span></tt></a>
<strong id="grammar-token-decimalinteger">decimalinteger</strong> ::= <a class="reference internal" href="#grammar-token-nonzerodigit"><tt class="xref docutils literal"><span class="pre">nonzerodigit</span></tt></a> <a class="reference internal" href="#grammar-token-digit"><tt class="xref docutils literal"><span class="pre">digit</span></tt></a>* | "0"+
<strong id="grammar-token-nonzerodigit">nonzerodigit </strong> ::= "1"..."9"
<strong id="grammar-token-digit">digit </strong> ::= "0"..."9"
<strong id="grammar-token-octinteger">octinteger </strong> ::= "0" ("o" | "O") <a class="reference internal" href="#grammar-token-octdigit"><tt class="xref docutils literal"><span class="pre">octdigit</span></tt></a>+
<strong id="grammar-token-hexinteger">hexinteger </strong> ::= "0" ("x" | "X") <a class="reference internal" href="#grammar-token-hexdigit"><tt class="xref docutils literal"><span class="pre">hexdigit</span></tt></a>+
<strong id="grammar-token-bininteger">bininteger </strong> ::= "0" ("b" | "B") <a class="reference internal" href="#grammar-token-bindigit"><tt class="xref docutils literal"><span class="pre">bindigit</span></tt></a>+
<strong id="grammar-token-octdigit">octdigit </strong> ::= "0"..."7"
<strong id="grammar-token-hexdigit">hexdigit </strong> ::= <a class="reference internal" href="#grammar-token-digit"><tt class="xref docutils literal"><span class="pre">digit</span></tt></a> | "a"..."f" | "A"..."F"
<strong id="grammar-token-bindigit">bindigit </strong> ::= "0" | "1"
</pre>
<p>There is no limit for the length of integer literals apart from what can be
stored in available memory.</p>
<p>Note that leading zeros in a non-zero decimal number are not allowed. This is
for disambiguation with C-style octal literals, which Python used before version
3.0.</p>
<p>Some examples of integer literals:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="mi">7</span> <span class="mi">2147483647</span> <span class="mo">0o177</span> <span class="m-Bin">0b100110111</span>
<span class="mi">3</span> <span class="mi">79228162514264337593543950336</span> <span class="mo">0o377</span> <span class="mh">0x100000000</span>
<span class="mi">79228162514264337593543950336</span> <span class="mh">0xdeadbeef</span>
</pre></div>
</div>
</div>
<div class="section" id="floating-point-literals">
<span id="floating"></span><h3>2.4.5. Floating point literals<a class="headerlink" href="#floating-point-literals" title="Permalink to this headline">¶</a></h3>
<p>Floating point literals are described by the following lexical definitions:</p>
<pre>
<strong id="grammar-token-floatnumber">floatnumber </strong> ::= <a class="reference internal" href="#grammar-token-pointfloat"><tt class="xref docutils literal"><span class="pre">pointfloat</span></tt></a> | <a class="reference internal" href="#grammar-token-exponentfloat"><tt class="xref docutils literal"><span class="pre">exponentfloat</span></tt></a>
<strong id="grammar-token-pointfloat">pointfloat </strong> ::= [<a class="reference internal" href="#grammar-token-intpart"><tt class="xref docutils literal"><span class="pre">intpart</span></tt></a>] <a class="reference internal" href="#grammar-token-fraction"><tt class="xref docutils literal"><span class="pre">fraction</span></tt></a> | <a class="reference internal" href="#grammar-token-intpart"><tt class="xref docutils literal"><span class="pre">intpart</span></tt></a> "."
<strong id="grammar-token-exponentfloat">exponentfloat</strong> ::= (<a class="reference internal" href="#grammar-token-intpart"><tt class="xref docutils literal"><span class="pre">intpart</span></tt></a> | <a class="reference internal" href="#grammar-token-pointfloat"><tt class="xref docutils literal"><span class="pre">pointfloat</span></tt></a>) <a class="reference internal" href="#grammar-token-exponent"><tt class="xref docutils literal"><span class="pre">exponent</span></tt></a>
<strong id="grammar-token-intpart">intpart </strong> ::= <a class="reference internal" href="#grammar-token-digit"><tt class="xref docutils literal"><span class="pre">digit</span></tt></a>+
<strong id="grammar-token-fraction">fraction </strong> ::= "." <a class="reference internal" href="#grammar-token-digit"><tt class="xref docutils literal"><span class="pre">digit</span></tt></a>+
<strong id="grammar-token-exponent">exponent </strong> ::= ("e" | "E") ["+" | "-"] <a class="reference internal" href="#grammar-token-digit"><tt class="xref docutils literal"><span class="pre">digit</span></tt></a>+
</pre>
<p>Note that the integer and exponent parts are always interpreted using radix 10.
For example, <tt class="docutils literal"><span class="pre">077e010</span></tt> is legal, and denotes the same number as <tt class="docutils literal"><span class="pre">77e10</span></tt>. The
allowed range of floating point literals is implementation-dependent. Some
examples of floating point literals:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="mf">3.14</span> <span class="mf">10.</span> <span class="o">.</span><span class="mi">001</span> <span class="mi">1</span><span class="n">e100</span> <span class="mf">3.14e-10</span> <span class="mi">0</span><span class="n">e0</span>
</pre></div>
</div>
<p>Note that numeric literals do not include a sign; a phrase like <tt class="docutils literal"><span class="pre">-1</span></tt> is
actually an expression composed of the unary operator <tt class="docutils literal"><span class="pre">-</span></tt> and the literal
<tt class="docutils literal"><span class="pre">1</span></tt>.</p>
</div>
<div class="section" id="imaginary-literals">
<span id="imaginary"></span><h3>2.4.6. Imaginary literals<a class="headerlink" href="#imaginary-literals" title="Permalink to this headline">¶</a></h3>
<p>Imaginary literals are described by the following lexical definitions:</p>
<pre>
<strong id="grammar-token-imagnumber">imagnumber</strong> ::= (<a class="reference internal" href="#grammar-token-floatnumber"><tt class="xref docutils literal"><span class="pre">floatnumber</span></tt></a> | <a class="reference internal" href="#grammar-token-intpart"><tt class="xref docutils literal"><span class="pre">intpart</span></tt></a>) ("j" | "J")
</pre>
<p>An imaginary literal yields a complex number with a real part of 0.0. Complex
numbers are represented as a pair of floating point numbers and have the same
restrictions on their range. To create a complex number with a nonzero real
part, add a floating point number to it, e.g., <tt class="docutils literal"><span class="pre">(3+4j)</span></tt>. Some examples of
imaginary literals:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="mf">3.14</span><span class="n">j</span> <span class="mf">10.</span><span class="n">j</span> <span class="mi">10</span><span class="n">j</span> <span class="o">.</span><span class="mi">001</span><span class="n">j</span> <span class="mi">1</span><span class="n">e100j</span> <span class="mf">3.14e-10</span><span class="n">j</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="operators">
<span id="id10"></span><h2>2.5. Operators<a class="headerlink" href="#operators" title="Permalink to this headline">¶</a></h2>
<p id="index-886">The following tokens are operators:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="o">+</span> <span class="o">-</span> <span class="o">*</span> <span class="o">**</span> <span class="o">/</span> <span class="o">//</span> <span class="o">%</span>
<span class="o"><<</span> <span class="o">>></span> <span class="o">&</span> <span class="o">|</span> <span class="o">^</span> <span class="o">~</span>
<span class="o"><</span> <span class="o">></span> <span class="o"><=</span> <span class="o">>=</span> <span class="o">==</span> <span class="o">!=</span>
</pre></div>
</div>
</div>
<div class="section" id="delimiters">
<span id="id11"></span><h2>2.6. Delimiters<a class="headerlink" href="#delimiters" title="Permalink to this headline">¶</a></h2>
<p id="index-887">The following tokens serve as delimiters in the grammar:</p>
<div class="highlight-python3"><pre>( ) [ ] { }
, : . ; @ =
+= -= *= /= //= %=
&= |= ^= >>= <<= **=</pre>
</div>
<p>The period can also occur in floating-point and imaginary literals. A sequence
of three periods has a special meaning as an ellipsis literal. The second half
of the list, the augmented assignment operators, serve lexically as delimiters,
but also perform an operation.</p>
<p>The following printing ASCII characters have special meaning as part of other
tokens or are otherwise significant to the lexical analyzer:</p>
<div class="highlight-python3"><div class="highlight"><pre><span class="s">' " # </span><span class="se">\</span>
</pre></div>
</div>
<p>The following printing ASCII characters are not used in Python. Their
occurrence outside string literals and comments is an unconditional error:</p>
<div class="highlight-python3"><pre>$ ?</pre>
</div>
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<h3><a href="../contents.html">Table Of Contents</a></h3>
<ul>
<li><a class="reference external" href="">2. Lexical analysis</a><ul>
<li><a class="reference external" href="#line-structure">2.1. Line structure</a><ul>
<li><a class="reference external" href="#logical-lines">2.1.1. Logical lines</a></li>
<li><a class="reference external" href="#physical-lines">2.1.2. Physical lines</a></li>
<li><a class="reference external" href="#comments">2.1.3. Comments</a></li>
<li><a class="reference external" href="#encoding-declarations">2.1.4. Encoding declarations</a></li>
<li><a class="reference external" href="#explicit-line-joining">2.1.5. Explicit line joining</a></li>
<li><a class="reference external" href="#implicit-line-joining">2.1.6. Implicit line joining</a></li>
<li><a class="reference external" href="#blank-lines">2.1.7. Blank lines</a></li>
<li><a class="reference external" href="#indentation">2.1.8. Indentation</a></li>
<li><a class="reference external" href="#whitespace-between-tokens">2.1.9. Whitespace between tokens</a></li>
</ul>
</li>
<li><a class="reference external" href="#other-tokens">2.2. Other tokens</a></li>
<li><a class="reference external" href="#identifiers">2.3. Identifiers and keywords</a><ul>
<li><a class="reference external" href="#keywords">2.3.1. Keywords</a></li>
<li><a class="reference external" href="#reserved-classes-of-identifiers">2.3.2. Reserved classes of identifiers</a></li>
</ul>
</li>
<li><a class="reference external" href="#literals">2.4. Literals</a><ul>
<li><a class="reference external" href="#string-and-bytes-literals">2.4.1. String and Bytes literals</a></li>
<li><a class="reference external" href="#string-literal-concatenation">2.4.2. String literal concatenation</a></li>
<li><a class="reference external" href="#numeric-literals">2.4.3. Numeric literals</a></li>
<li><a class="reference external" href="#integer-literals">2.4.4. Integer literals</a></li>
<li><a class="reference external" href="#floating-point-literals">2.4.5. Floating point literals</a></li>
<li><a class="reference external" href="#imaginary-literals">2.4.6. Imaginary literals</a></li>
</ul>
</li>
<li><a class="reference external" href="#operators">2.5. Operators</a></li>
<li><a class="reference external" href="#delimiters">2.6. Delimiters</a></li>
</ul>
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