diff options
| -rw-r--r-- | Grammar/Grammar | 110 |
1 files changed, 10 insertions, 100 deletions
diff --git a/Grammar/Grammar b/Grammar/Grammar index 771e47f..1e9ce77 100644 --- a/Grammar/Grammar +++ b/Grammar/Grammar @@ -1,100 +1,6 @@ # Grammar for Python -# Change log: - -# 17-Aug-94: -# Added #diagram:... comments for Kees Blom's railroad diagram generator - -# 3-May-94: -# Added else clause to try-except - -# 17-Apr-94: -# Added string literal concatenation - -# 13-Apr-94: -# Added default values for function/lambda argument lists - -# 30-Nov-93: -# Removed lambda_input, added lambdef - -# 25-Oct-93: -# Added lambda_input - -# 18-Oct-93: -# Use testlist instead of exprlist in expr_stmt -# Add exec statement - -# 19-May-93: -# Add access statement - -# 18-May-93: -# Abolish old class header syntax - -# 06-Apr-92: -# Use only '*' for varargs list - -# 31-Mar-92: -# Tighten syntax for try statements - -# 27-Feb-92: -# Allow NEWLINE* after eval input - -# 16-Jan-92: -# Added '*' as alternative for '+' in varargs syntax -# (Not sure which alternative is better yet.) - -# 11-Jan-92: -# Variable length argument list syntax added: def f(a, b, +rest): ... - -# 8-Jan-92: -# Allow only '==' for equality testing - -# Changes since version 8: -# Trailing commas in formal parameter lists are allowed - -# Changes since version 7: -# New syntax to specify base classes (but old syntax retained for now) -# 'global' statement (valid only in functions but not enforced here) - -# Changes since version 6: -# Add logical operators '|', '^', '&' and '~' -# Add shift operators '<<' and '>>' - -# Changes since version 5: -# Comparison operators '<=' '>' '<>' are now 1 token -# Also support '!=' and '==' as alternatives for '<>' and '=' - -# Changes compared to version 4: -# Blank lines and lines only containing a comment are now eaten -# by the lexer, so the NEWLINE* things in suite are gone -# (but the 2nd NEWLINE terminating single_input stays!) -# Semicolons can separate small statements -# 'continue' statement -# Dictionary constructors: {key:value, key:value, ...} -# More tests instead of exprs - -# Changes compared to version 3: -# Removed 'dir' statement. -# Function call argument is a testlist instead of exprlist. - -# Changes compared to version 2: -# The syntax of Boolean operations is changed to use more -# conventional priorities: or < and < not. - -# Changes compared to version 1: -# modules and scripts are unified; -# 'quit' is gone (use ^D); -# empty_stmt is gone, replaced by explicit NEWLINE where appropriate; -# 'import' and 'def' aren't special any more; -# added 'from' NAME option on import clause, and '*' to import all; -# added class definition. - -# Start symbols for the grammar: -# single_input is a single interactive statement; -# file_input is a module or sequence of commands read from an input file; -# eval_input is the input for the eval() and input() functions. - -# NB: compound_stmt in single_input is followed by extra NEWLINE! +# Commands for Kees Blom's railroad program #diagram:token NAME #diagram:token NUMBER #diagram:token STRING @@ -105,6 +11,12 @@ #diagram:token DEDENT #diagram:output\textwidth 20.04cm\oddsidemargin 0.0cm\evensidemargin 0.0cm #diagram:rules + +# Start symbols for the grammar: +# single_input is a single interactive statement; +# file_input is a module or sequence of commands read from an input file; +# eval_input is the input for the eval() and input() functions. +# NB: compound_stmt in single_input is followed by extra NEWLINE! single_input: NEWLINE | simple_stmt | compound_stmt NEWLINE file_input: (NEWLINE | stmt)* ENDMARKER eval_input: testlist NEWLINE* ENDMARKER @@ -118,7 +30,7 @@ fplist: fpdef (',' fpdef)* [','] stmt: simple_stmt | compound_stmt simple_stmt: small_stmt (';' small_stmt)* [';'] NEWLINE small_stmt: expr_stmt | print_stmt | del_stmt | pass_stmt | flow_stmt | import_stmt | global_stmt | access_stmt | exec_stmt -expr_stmt: (testlist '=')* testlist +expr_stmt: testlist ('=' testlist)* # For assignments, additional restrictions enforced by the interpreter print_stmt: 'print' (test ',')* [test] del_stmt: 'del' exprlist @@ -130,16 +42,14 @@ return_stmt: 'return' [testlist] raise_stmt: 'raise' test [',' test] import_stmt: 'import' NAME (',' NAME)* | 'from' NAME 'import' ('*' | NAME (',' NAME)*) global_stmt: 'global' NAME (',' NAME)* -access_stmt: ('access' ('*' | NAME (',' NAME)*) ':' #diagram:break - accesstype (',' accesstype)*) +access_stmt: 'access' ('*' | NAME (',' NAME)*) ':' accesstype (',' accesstype)* accesstype: NAME+ # accesstype should be ('public' | 'protected' | 'private') ['read'] ['write'] # but can't be because that would create undesirable reserved words! exec_stmt: 'exec' expr ['in' test [',' test]] compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | funcdef | classdef -if_stmt: ('if' test ':' suite ('elif' test ':' suite)* #diagram:break - ['else' ':' suite]) +if_stmt: 'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite] while_stmt: 'while' test ':' suite ['else' ':' suite] for_stmt: 'for' exprlist 'in' testlist ':' suite ['else' ':' suite] try_stmt: ('try' ':' suite (except_clause ':' suite)+ #diagram:break |