32.5. token — Constants used with Python parse trees - Python 2.7.18 documentation 编辑

Source code: Lib/token.py

This module provides constants which represent the numeric values of leaf nodes of the parse tree (terminal tokens). Refer to the file Grammar/Grammar in the Python distribution for the definitions of the names in the context of the language grammar. The specific numeric values which the names map to may change between Python versions.

The module also provides a mapping from numeric codes to names and some functions. The functions mirror definitions in the Python C header files.

token.tok_name

Dictionary mapping the numeric values of the constants defined in this module back to name strings, allowing more human-readable representation of parse trees to be generated.

token.ISTERMINAL(x)

Return true for terminal token values.

token.ISNONTERMINAL(x)

Return true for non-terminal token values.

token.ISEOF(x)

Return true if x is the marker indicating the end of input.

The token constants are:

token.ENDMARKER

token.NAME

token.NUMBER

token.STRING

token.NEWLINE

token.INDENT

token.DEDENT

token.LPAR

token.RPAR

token.LSQB

token.RSQB

token.COLON

token.COMMA

token.SEMI

token.PLUS

token.MINUS

token.STAR

token.SLASH

token.VBAR

token.AMPER

token.LESS

token.GREATER

token.EQUAL

token.DOT

token.PERCENT

token.BACKQUOTE

token.LBRACE

token.RBRACE

token.EQEQUAL

token.NOTEQUAL

token.LESSEQUAL

token.GREATEREQUAL

token.TILDE

token.CIRCUMFLEX

token.LEFTSHIFT

token.RIGHTSHIFT

token.DOUBLESTAR

token.PLUSEQUAL

token.MINEQUAL

token.STAREQUAL

token.SLASHEQUAL

token.PERCENTEQUAL

token.AMPEREQUAL

token.VBAREQUAL

token.CIRCUMFLEXEQUAL

token.LEFTSHIFTEQUAL

token.RIGHTSHIFTEQUAL

token.DOUBLESTAREQUAL

token.DOUBLESLASH

token.DOUBLESLASHEQUAL

token.AT

token.OP

token.ERRORTOKEN

token.N_TOKENS

token.NT_OFFSET

See also

Module parser

The second example for the parser module shows how to use the symbol module.