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-rw-r--r--Grammar/Grammar110
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