ó
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Y\¬Qc @ sF d Z d d l m Z d e f d YZ d e f d YZ d S( sÈ Parser engine for the grammar tables generated by pgen.
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The grammar table must be loaded first.
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See Parser/parser.c in the Python distribution for additional info on
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how this parsing engine works.
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i ( t tokent
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ParseErrorc B s e Z d Z d Z RS( s( Exception to signal the parser is stuck.c C sH t j | d | | | | f | | _ | | _ | | _ | | _ d S( Ns! %s: type=%r, value=%r, context=%r( t Exceptiont __init__t msgt typet valuet context( t selfR R R R ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyR s ( t __name__t
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__module__t __doc__R ( ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyR s t Parserc B sS e Z d Z d d Z d d Z d Z d Z d Z d Z d Z
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RS( s5 Parser engine.
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The proper usage sequence is:
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p = Parser(grammar, [converter]) # create instance
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p.setup([start]) # prepare for parsing
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<for each input token>:
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if p.addtoken(...): # parse a token; may raise ParseError
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break
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root = p.rootnode # root of abstract syntax tree
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A Parser instance may be reused by calling setup() repeatedly.
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A Parser instance contains state pertaining to the current token
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sequence, and should not be used concurrently by different threads
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to parse separate token sequences.
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See driver.py for how to get input tokens by tokenizing a file or
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string.
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Parsing is complete when addtoken() returns True; the root of the
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abstract syntax tree can then be retrieved from the rootnode
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instance variable. When a syntax error occurs, addtoken() raises
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the ParseError exception. There is no error recovery; the parser
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cannot be used after a syntax error was reported (but it can be
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reinitialized by calling setup()).
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c C s | | _ | p d | _ d S( sÚ Constructor.
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The grammar argument is a grammar.Grammar instance; see the
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grammar module for more information.
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The parser is not ready yet for parsing; you must call the
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setup() method to get it started.
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The optional convert argument is a function mapping concrete
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syntax tree nodes to abstract syntax tree nodes. If not
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given, no conversion is done and the syntax tree produced is
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the concrete syntax tree. If given, it must be a function of
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two arguments, the first being the grammar (a grammar.Grammar
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instance), and the second being the concrete syntax tree node
|
to be converted. The syntax tree is converted from the bottom
|
up.
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A concrete syntax tree node is a (type, value, context, nodes)
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tuple, where type is the node type (a token or symbol number),
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value is None for symbols and a string for tokens, context is
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None or an opaque value used for error reporting (typically a
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(lineno, offset) pair), and nodes is a list of children for
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symbols, and None for tokens.
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An abstract syntax tree node may be anything; this is entirely
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up to the converter function.
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c S s | S( N( ( t grammart node( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyt <lambda>W s N( R t convert( R R R ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyR 9 s c C sk | d k r | j j } n | d d g f } | j j | d | f } | g | _ d | _ t | _ d S( s Prepare for parsing.
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This *must* be called before starting to parse.
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The optional argument is an alternative start symbol; it
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defaults to the grammar's start symbol.
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You can use a Parser instance to parse any number of programs;
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each time you call setup() the parser is reset to an initial
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state determined by the (implicit or explicit) start symbol.
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i N( t NoneR t startt dfast stackt rootnodet sett
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used_names( R R t newnodet
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stackentry( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyt setupY s c C sÆ | j | | | } xªt rÁ| j d \ } } } | \ } } | | }
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D]\ } } | j j | \ } } | | k r
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| d k s t | j | | | | | } xV | | d | f g k r| j | j sà t S| j d \ } } } | \ } } q° Wt S| d k rQ | j j | } | \ } } | | k re| j
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| | j j | | | PqeqQ qQ Wd | f |
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k r©| j | j s¾t d | | | q¾q t d | | | q Wd S( s< Add a token; return True iff this is the end of the program.iÿÿÿÿi i s too much inputs bad inputN( t classifyt TrueR R t labelst AssertionErrort shiftt popt FalseR t pushR ( R R R R t ilabelt dfat stateR t statest firstt arcst it newstatet tt vt itsdfat itsstatest itsfirst( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyt addtokenq s<
|
|
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c C s | t j k rG | j j | | j j j | } | d k rG | Sn | j j j | } | d k r t d | | | n | S( s& Turn a token into a label. (Internal)s bad tokenN(
|
R t NAMER t addR t keywordst getR t tokensR ( R R R R R# ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyR ¡ s c C sw | j d \ } } } | | | d f } | j | j | } | d k r] | d j | n | | | f | j d <d S( s Shift a token. (Internal)iÿÿÿÿN( R R R R t append( R R R R* R R$ R% R R ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyR ¯ s c C s[ | j d \ } } } | d | g f } | | | f | j d <| j j | d | f d S( s Push a nonterminal. (Internal)iÿÿÿÿi N( R R R6 ( R R t newdfaR* R R$ R% R R ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyR" ¸ s c C s | j j \ } } } | j | j | } | d k r | j rl | j d \ } } } | d j | q | | _ | j | j _ n d S( s Pop a nonterminal. (Internal)iÿÿÿÿN( R R R R R R6 R R ( R t popdfat popstatet popnodeR R$ R% R ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyR ¿ s N( R R
|
R R R R R0 R R R" R ( ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyR s 0 N( R t R R R t objectR ( ( ( s[ /tmp/ndk-User/buildhost/install/prebuilt/darwin-x86_64/lib/python2.7/lib2to3/pgen2/parse.pyt <module> s
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