| 1 | # Demo of grammar for Oil.
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| 2 | #
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| 3 | # We might use pgen2 for the expression language, since there are many cases
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| 4 | # that don't fit within the model of Pratt parsing (literals, list
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| 5 | # comprehensions, type expressions, etc.)
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| 6 | 
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| 7 | # Start symbols for the grammar:
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| 8 | #       single_input is a single interactive statement;
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| 9 | #       file_input is a module or sequence of commands read from an input file;
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| 10 | #       eval_input is the input for the eval() and input() functions.
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| 11 | # NB: compound_stmt in single_input is followed by extra NEWLINE!
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| 12 | single_input: NEWLINE | simple_stmt | compound_stmt NEWLINE
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| 13 | file_input: (NEWLINE | stmt)* ENDMARKER
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| 14 | eval_input: testlist NEWLINE* ENDMARKER
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| 15 | 
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| 16 | # added for Oil
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| 17 | arglist_input: arglist NEWLINE* ENDMARKER
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| 18 | 
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| 19 | funcdef: 'def' NAME parameters ':' suite
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| 20 | parameters: '(' [varargslist] ')'
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| 21 | varargslist: ((fpdef ['=' test] ',')*
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| 22 |               ('*' NAME [',' '**' NAME] | '**' NAME) |
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| 23 |               fpdef ['=' test] (',' fpdef ['=' test])* [','])
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| 24 | fpdef: NAME | '(' fplist ')'
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| 25 | fplist: fpdef (',' fpdef)* [',']
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| 26 | 
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| 27 | stmt: simple_stmt | compound_stmt
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| 28 | simple_stmt: small_stmt (';' small_stmt)* [';'] NEWLINE
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| 29 | small_stmt: (expr_stmt | print_stmt  | del_stmt | pass_stmt | flow_stmt |
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| 30 |              assert_stmt)
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| 31 | expr_stmt: testlist (augassign (yield_expr|testlist) |
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| 32 |                      ('=' (yield_expr|testlist))*)
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| 33 | augassign: ('+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | 'xor=' |
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| 34 |             '<<=' | '>>=' | '^=' | 'div=')
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| 35 | # For normal assignments, additional restrictions enforced by the interpreter
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| 36 | print_stmt: 'print' ( [ test (',' test)* [','] ] |
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| 37 |                       '>>' test [ (',' test)+ [','] ] )
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| 38 | del_stmt: 'del' exprlist
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| 39 | pass_stmt: 'pass'
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| 40 | flow_stmt: break_stmt | continue_stmt | return_stmt | raise_stmt | yield_stmt
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| 41 | break_stmt: 'break'
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| 42 | continue_stmt: 'continue'
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| 43 | return_stmt: 'return' [testlist]
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| 44 | yield_stmt: yield_expr
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| 45 | raise_stmt: 'raise' [test [',' test [',' test]]]
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| 46 | assert_stmt: 'assert' test [',' test]
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| 47 | 
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| 48 | compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | with_stmt | funcdef | classdef
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| 49 | if_stmt: 'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite]
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| 50 | while_stmt: 'while' test ':' suite ['else' ':' suite]
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| 51 | for_stmt: 'for' exprlist 'in' testlist ':' suite ['else' ':' suite]
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| 52 | try_stmt: ('try' ':' suite
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| 53 |            ((except_clause ':' suite)+
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| 54 |             ['else' ':' suite]
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| 55 |             ['finally' ':' suite] |
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| 56 |            'finally' ':' suite))
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| 57 | with_stmt: 'with' with_item (',' with_item)*  ':' suite
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| 58 | with_item: test ['as' expr]
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| 59 | # NB compile.c makes sure that the default except clause is last
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| 60 | except_clause: 'except' [test [('as' | ',') test]]
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| 61 | suite: simple_stmt  # removed
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| 62 | 
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| 63 | # Backward compatibility cruft to support:
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| 64 | # [ x for x in lambda: True, lambda: False if x() ]
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| 65 | # even while also allowing:
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| 66 | # lambda x: 5 if x else 2
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| 67 | # (But not a mix of the two)
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| 68 | testlist_safe: old_test [(',' old_test)+ [',']]
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| 69 | old_test: or_test | old_lambdef
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| 70 | old_lambdef: 'lambda' [varargslist] ':' old_test
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| 71 | 
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| 72 | test: or_test ['if' or_test 'else' test] | lambdef
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| 73 | or_test: and_test ('or' and_test)*
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| 74 | and_test: not_test ('and' not_test)*
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| 75 | not_test: 'not' not_test | comparison
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| 76 | comparison: expr (comp_op expr)*
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| 77 | comp_op: '<'|'>'|'=='|'>='|'<='|'!='|'in'|'not' 'in'|'is'|'is' 'not'
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| 78 | expr: xor_expr ('|' xor_expr)*
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| 79 | xor_expr: and_expr ('^' and_expr)*
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| 80 | and_expr: shift_expr ('&' shift_expr)*
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| 81 | shift_expr: arith_expr (('<<'|'>>') arith_expr)*
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| 82 | arith_expr: term (('+'|'-') term)*
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| 83 | term: factor (('*'|'/'|'%'|'div') factor)*
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| 84 | factor: ('+'|'-'|'~') factor | power
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| 85 | power: atom trailer* ['^' factor]
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| 86 | atom: ('(' [yield_expr|testlist_comp] ')' |
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| 87 |        '[' [listmaker] ']' |
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| 88 |        '{' [dictorsetmaker] '}' |
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| 89 |        NAME | NUMBER)  # removed string!
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| 90 | listmaker: test ( list_for | (',' test)* [','] )
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| 91 | testlist_comp: test ( comp_for | (',' test)* [','] )
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| 92 | lambdef: 'lambda' [varargslist] ':' test
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| 93 | trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME
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| 94 | subscriptlist: subscript (',' subscript)* [',']
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| 95 | subscript: '.' '.' '.' | test | [test] ':' [test] [sliceop]
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| 96 | sliceop: ':' [test]
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| 97 | exprlist: expr (',' expr)* [',']
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| 98 | testlist: test (',' test)* [',']
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| 99 | dictorsetmaker: ( (test ':' test (comp_for | (',' test ':' test)* [','])) |
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| 100 |                   (test (comp_for | (',' test)* [','])) )
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| 101 | 
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| 102 | classdef: 'class' NAME ['(' [testlist] ')'] ':' suite
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| 103 | 
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| 104 | arglist: (argument ',')* (argument [',']
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| 105 |                          |'*' test (',' argument)* [',' '**' test] 
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| 106 |                          |'**' test)
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| 107 | # The reason that keywords are test nodes instead of NAME is that using NAME
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| 108 | # results in an ambiguity. ast.c makes sure it's a NAME.
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| 109 | argument: test [comp_for] | test '=' test
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| 110 | 
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| 111 | list_iter: list_for | list_if
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| 112 | list_for: 'for' exprlist 'in' testlist_safe [list_iter]
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| 113 | list_if: 'if' old_test [list_iter]
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| 114 | 
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| 115 | comp_iter: comp_for | comp_if
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| 116 | comp_for: 'for' exprlist 'in' or_test [comp_iter]
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| 117 | comp_if: 'if' old_test [comp_iter]
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| 118 | 
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| 119 | testlist1: test (',' test)*
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| 120 | 
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| 121 | yield_expr: 'yield' [testlist]
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| 122 | 
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| 123 | 
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| 124 | # Oil types are like MyPy types
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| 125 | # Python 3 uses the much more general "test" production.
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| 126 | 
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| 127 | type_expr: NAME ['<' type_expr (',' type_expr)* '>' ]
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| 128 | 
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| 129 | # added for Oil
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| 130 | type_input: type_expr NEWLINE* ENDMARKER
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| 131 | 
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