<<Grammar Name="python_2_5_2_i"
encoding_class="ascii"
reference="http://www.python.org/doc/2.5.2/ref/grammar.txt"
comment="'readable', but not optimized, heavily backtracking version of python grammar"
>>
{
bool init_()
{ in_raw_mode= false;
indentStack.Clear();
indentStack.Push(0);
indentLength_=-1;
return true;
}
#region raw string handling
bool in_raw_mode;
bool set_raw_(){in_raw_mode=true;return true;}
bool unset_raw_(){in_raw_mode=false;return true;}
bool in_raw_(){return in_raw_mode;}
#endregion raw string handling
#region implicit line joining
bool in_impl_line_join_;
bool in_implicit_line_joining_(){return in_impl_line_join_;}
bool set_implicit_line_joining_(bool bOn,out bool prev)
{prev=in_impl_line_join_;in_impl_line_join_=bOn;return true;}
bool set_implicit_line_joining_(bool bOn)
{in_impl_line_join_=bOn;return true;}
#endregion implicit line joining
string indent_;
int indentLength_;//accounts for tabs
int indentLengthToRestore_;
System.Collections.Generic.Stack<int> indentStack= new System.Collections.Generic.Stack<int>();
int NormalizedIndentLength()
{
int indentLength = 0;
for (int i = 0; i < indent_.Length; ++i)
{
if (indent_[i] == '\t') indentLength += 8 - i % 8;
else indentLength++;
}
return indentLength;
}
bool continue_after_dedent_()
{
indentLengthToRestore_= indentLength_;
if( indentLength_== -1 ) return false;
if (indentLength_ == indentStack.Peek()){
indentLength_=-1;
return true;
}
return false;
}
bool RESTOREINDENT_(){indentLength_= indentLengthToRestore_;return false;}
bool keep_handler_()
{
if( indentLength_!=-1 ) return false;//indentation belongs to other block
indentLength_= NormalizedIndentLength();
bool kept= indentStack.Peek()== indentLength_;
if( kept ) indentLength_=-1;
return kept;
}
bool indent_handler_()
{
if( indentLength_!=-1 ) return false;//indentation belongs to other block
int indentLength = NormalizedIndentLength();
if (indentLength <= indentStack.Peek()) return false;
else{
indentStack.Push(indentLength);
indentLength_=-1;
return true;
}
}
bool dedent_handler_()
{
System.Diagnostics.Debug.Assert(indentStack.Count>1);
if (indentLength_ >= indentStack.Peek() || !indentStack.Contains(indentLength_)) return false;
else{
indentStack.Pop();
if( indentStack.Count==1 ) indentLength_=-1;
return true;
}
}
}
Line_join_sem_{
bool prev_;
Line_join_sem_(){set_implicit_line_joining_(true,out prev_);}
~Line_join_sem_(){set_implicit_line_joining_(prev_);}
}
[1] ^^interactive_input: (compound_stmt/stmt_list?)
( NEWLINE / FATAL<"syntax error: line break expected">);
[2] ^^file_input: init_ BLANKLINE* (NEWLINE / statement)* ENDMARKER
(!./FATAL<"wrong indent or non-python text here">);
[3] ^^eval_input: init_ expression_list NEWLINE* ENDMARKER;
[4] ^^input_input: init_ expression_list NEWLINE ENDMARKER;
[5] ^^atom: identifier S / literal / enclosure;
[6] enclosure: generator_expression / dict_display
/ string_conversion / yield_atom
/ parenth_form / list_display;
[7] literal : (STRING S)+ / NUMBER S ;
[8] parenth_form: '(' parenth_form_content @')' S;
[9] parenth_form_content
using Line_join_sem_: S expression_list?;
[10]^^list_display: '[' list_display_content @']' S;
[11] list_display_content
using Line_join_sem_: S (list_comprehension / expression_list )?;
[12]^^list_comprehension:expression list_for;
[13]^^list_for: 'for' S2 target_list @'in' S2 old_expression_list list_iter?;
[14]^^old_expression_list:
old_expression ((',' S old_expression)+ (','S)?)?;
[15]^^list_iter: list_for / list_if;
[16]^^list_if: 'if' S2 old_expression list_iter?;
[17]^^generator_expression:
'(' generator_expression_content @')' S;
[18]generator_expression_content
using Line_join_sem_: S expression genexpr_for;
[19]^^genexpr_for: 'for' S2 target_list @'in' S2 or_test genexpr_iter?;
[20]^^genexpr_iter: genexpr_for / genexpr_if;
[21]^^genexpr_if: 'if' S2 old_expression genexpr_iter?;
[22]^^dict_display: '{' dict_display_content @'}' S ;
[23] dict_display_content
using Line_join_sem_: S key_datum_list?;
[24]^^key_datum_list: key_datum (',' S key_datum)* (',' S)? ;
[25]^^key_datum: expression @':' S expression;
[26]^^string_conversion: '`' S expression_list @'`' S;
[27]^^yield_atom: '(' yield_atom_content @')' S;
[28]yield_atom_content
using Line_join_sem_: S yield_expression;
[29]^^yield_expression: 'yield' S2 expression_list?;
[30] ^primary: atom (attributeref / slicing / call_args)*;
[31]^^attributeref: '.' S @identifier S;
[32]^^slicing: '[' slicing_content @']' S;
[33]slicing_content
using Line_join_sem_: S slice_list;
[34]^^slice_list: slice_item (',' S slice_item)* (','S)?;
[35]^^slice_item: ellipsis / slice / expression ;
[36]^^slice: lower_bound? ':' S upper_bound? stride?;
[37]^^stride: ':' S expression?;
[38]^^lower_bound: expression;
[39]^^upper_bound: expression;
[40]^^ellipsis: '.' S '.' S '.' S; // or '...' ?
[41]^^call_args: '(' call_args_content @')' S;
[42] call_args_content
using Line_join_sem_ :S (expression genexpr_for / argument_list (',' S)? )?;
[43]^^argument_list: keyword_arguments seq_arg? dict_arg?
/ positional_arguments ((',' S) keyword_arguments)? seq_arg? dict_arg?
/ seq_arg dict_arg?
/ dict_arg;
[44]^^seq_arg: ',' S '*' S expression;
[45]^^dict_arg: ',' S '**' S expression;
[46]^^positional_arguments:
expression (',' S !keyword_item expression)*;
[47]^^keyword_arguments: keyword_item (',' S keyword_item)*;
[48]^^keyword_item: identifier S '=' S expression;
[49] ^power: primary ('**' S @u_expr)?;
[50] ^u_expr: power / ^'-' S @u_expr / ^'+' S @u_expr / ^'~' S @u_expr;
[51] ^m_expr: u_expr (^('*'/'//'/'/'/'%') S u_expr)*;
[52] ^a_expr: m_expr ( ^[+-] S @m_expr)*;
[53] ^shift_expr: a_expr (^('<<' / '>>' ) S @a_expr)*;
[54] ^and_expr: shift_expr ('&' S @shift_expr)*;
[55] ^xor_expr: and_expr ( '^' S @and_expr)*;
[56] ^or_expr: xor_expr ( '|' S @xor_expr)*;
[57] ^comparison: or_expr ( comp_operator S @or_expr )*;
[58]^^comp_operator: '>=' / '<=' / '<>' / '<' / '>' / '==' / '!=' /
is_operator / in_operator;
[59]^^is_operator: 'is' S2 (not_symbol S2)? ;
[60]^^in_operator: (not_symbol S2)? 'in';
[61] expression: conditional_expression / lambda_form;
[62]^^old_expression: or_test / old_lambda_form;
[63]^^conditional_expression:
or_test ('if' S2 @or_test @(^'else') S2 expression)?;
[64] ^or_test: and_test ('or' S2 @and_test)*;
[65] ^and_test: not_test ( 'and' S2 @not_test)*;
[66] ^not_test: (not_symbol S2)* comparison;
[67]^^not_symbol: 'not';
[68]^^lambda_form: 'lambda' S2 parameter_list? @':' S expression;
[69]^^old_lambda_form: 'lambda' S2 parameter_list? @':' S old_expression;
[70] expression_list: expression ( ',' S expression )* (',' S)?;
[71] simple_stmt:
assert_stmt
/ pass_stmt
/ del_stmt
/ print_stmt
/ return_stmt
/ yield_stmt
/ raise_stmt
/ break_stmt
/ continue_stmt
/ import_stmt
/ global_stmt
/ exec_stmt
/ augmented_assignment_stmt
/ assignment_stmt
/ expression_stmt;
[72]^^expression_stmt: expression_list;
[73]^^assert_stmt: 'assert' S2 @expression (',' S @expression)?;
[74]^^assignment_stmt: (target_list '='!'=' S)+ @(expression_list / yield_expression);
[75]^^target_list: target (',' S target)* (',' S)?;
[76]^^target: '(' target_contents ')' S
/ '[' target_contents ']' S
/ assignable_primary;
[77]target_contents
using Line_join_sem_: S target_list;
[78]^^assignable_primary:
(identifier S/ enclosure !targetlist_end)
(attributeref / slicing / call_args !targetlist_end )*;
[79]^^targetlist_end: S ([,=] S / 'in' S2);
[80]^^augmented_assignment_stmt:
target augop S @(expression_list / yield_expression);
[81]^^augop: '+=' / '-=' / '*=' / '/=' / '%=' / '**='
/ '>>=' / '<<=' / '&=' / '^=' / '/=' / '//='; // '//=' added by me
[82]^^pass_stmt: 'pass' S2;
[83]^^del_stmt: 'del' S2 @target_list;
[84]^^print_stmt: 'print' S2 ( '>>' S expression (',' S expression)+ (',' S)?
/ expression (',' S expression)* (',' S)?
)?;
[85]^^return_stmt: 'return' S2 expression_list?;
[86]^^yield_stmt: yield_expression;
[87]^^raise_stmt: 'raise' S2 (expression (',' S expression (',' S expression)?)?)?;
[88]^^break_stmt: 'break' S2;
[89]^^continue_stmt: 'continue' S2;
[90]^^import_stmt: import_name / import_from;
[91]^^import_name: 'import' S2 module import_as? ( ',' S module import_as? )*;
[92]^^import_from: 'from' S2 module @'import' S '*' S
/ 'from' S2 relative_module @'import' S2
(imports_in_parens / imports_list);
[93]^^import_as: 'as' S2 @name;
[94]^^imports_in_parens: '(' imports_in_parens_content @')' S;
[95] imports_in_parens_content:
S2 identifier S import_as? rest_import_list (',' S)?;
[96]^^imports_list: identifier S import_as? rest_import_list;
[97]^^rest_import_list: (',' S identifier S import_as? )*;
[98]^^module: (identifier S '.' S)* identifier S;
[99]^^relative_module: ('.' S)* module / ('.' S)+;
[100]^^name: identifier S;
[101]^^global_stmt: 'global' S2 @identifier S (',' S @identifier S)*;
[102]^^exec_stmt: 'exec' S2 or_expr ('in' S2 expression (',' S expression)?)?;
[103]^^compound_stmt: if_stmt / while_stmt / for_stmt / try_stmt / with_stmt
/ funcdef / classdef;
[104]^^suite: stmt_list @(NEWLINE/ENDMARKER) /
NEWLINE INDENT @statement (KEEPINDENT @statement)* DEDENT;
[105] statement: compound_stmt / stmt_list (NEWLINE/ENDMARKER);
[106] stmt_list: simple_stmt (';' S simple_stmt)* (';' S)? ;
[107]^^if_stmt: 'if' S2 @expression @':' S suite
(KEEPINDENT ^'elif' S2 @expression @':' S suite / RESTOREINDENT_ )*
(KEEPINDENT ^'else' S @':' S suite / RESTOREINDENT_ )?;
[108]^^while_stmt: 'while' S2 @expression @':' S suite
(KEEPINDENT 'else' S @':' S suite / RESTOREINDENT_ )?;
[109]^^for_stmt: 'for' S2 target_list @'in' S2 expression_list
@':' S suite (KEEPINDENT 'else' S @':' S suite / RESTOREINDENT_ )?;
[110]^^try_stmt: 'try' S @':' S suite ( except_handler / finally_only_handler );
[111]^^finally_only_handler:
KEEPINDENT 'finally' S @':' S suite / RESTOREINDENT_ ;
[112]^^except_handler: (KEEPINDENT ^'except' S2 (expression (',' S target)?)? @':' S suite / RESTOREINDENT_ )+
(KEEPINDENT ^'else' S @':' S suite / RESTOREINDENT_ )? finally_only_handler?;
[113]^^with_stmt: 'with' S2 expression ('as' S2 @target)? @':' S suite;
[114]^^funcdef: decorators? 'def' S2 @funcname S '(' parameter_list_in @')' S @':' S suite;
[115] parameter_list_in
using Line_join_sem_: S parameter_list?;
[116]^^decorators: decorator+;
[117]^^decorator: '@' S dotted_name ('(' decorater_in @')' S)? NEWLINE
(KEEPINDENT/FATAL<"decorator continuation incorrectly indented">);
[118] decorater_in
using Line_join_sem_: S (argument_list (','S)?)?;
[119]^^dotted_name: identifier S('.' S identifier S)*;
[120]^^parameter_list: defparameter (',' S defparameter )* (',' S seq_dict_pars?)? / seq_dict_pars;
[121]^^seq_dict_pars: ('*' S identifier S (',' S '**' S identifier S)? / '**' S identifier S);
[122]^^defparameter: parameter ('=' S @expression)?;
[123]^^sublist: parameter (',' S parameter)* ','?;
[124]^^parameter: identifier S / '(' parameter_in @')' S;
[125] parameter_in: S @sublist;
[126]^^funcname: identifier;
[127]^^classdef: 'class' S classname S inheritance? ':' S suite;
[128]^^inheritance
using Line_join_sem_: '(' S expression_list? @')' S;
[129]^^classname: identifier;
//token definitions added for PEG following the docs at python.org
[130] S: ( [ \t\v\f]+ /
COMMENT /
'\\' NL /
NL in_implicit_line_joining_
)* ;
[131]S2: ![A-Za-z_0-9] S;
[132]^^identifier: !(KEYWORD S2) [A-Za-z_][A-Za-z0-9_]*;
[133]INDENT: S:indent_ (indent_handler_/FATAL<"indentation error">);
[134]KEEPINDENT: continue_after_dedent_ / S:indent_ keep_handler_;
[135]DEDENT: S dedent_handler_/FATAL<"indentation error">;
[136]NEWLINE: NL BLANKLINE*;
[137]NL: '\r'?'\n' / '\n' / '\r' ;
[138]BLANKLINE: [ \t\v\f]* COMMENT? NL/ [ \t\v\f]+ COMMENT? !. / COMMENT !. ;
[139]NAME: !(KEYWORD S2) [A-Za-z_][A-Za-z0-9_]* S;
[140]IDENT: [A-Za-z_][A-Za-z0-9_]*;
[141]KEYWORD:
('and' / 'del' / 'from' / 'not' / 'while' /
'as' / 'elif' / 'global' / 'or' / 'with' /
'assert' / 'else' / 'if' / 'pass' / 'yield' /
'break' / 'except' / 'import' / 'print' /
'class' / 'exec' / 'in' / 'raise' /
'continue' / 'finally' / 'is' / 'return' /
'def' / 'for' / 'lambda' / 'try') ;
[142]COMMENT: '#' (!NL.)*;
[143]ENDMARKER: !./WARNING<"file end expected">;
[144]NUMBER: imagnumber / floatnumber / integer ^([lL]?) ;
[145]STRING: stringprefix? (longstring/shortstring) unset_raw_;
[146]^^integer: [1-9][0-9]* / '0'[xX] [0-9a-fA-F]+ / '0'[0-7]*;
[147]^^floatnumber: pointfloat exponent? / [0-9]+ exponent;
[148]pointfloat: [0-9]* '.' [0-9]+ / [0-9]+ '.';
[149]exponent: [eE][+-]?[0-9]+;
[150]^^imagnumber: (floatnumber / [0-9]+) [jJ];
[151] stringprefix: raw_indicating_stringprefix / unicodeonly_stringprefix;
[152]^^raw_indicating_stringprefix:
('r' / 'ur' / 'R' / 'UR' / 'Ur' / 'uR') set_raw_;
[153]^^unicodeonly_stringprefix:
'u' / 'U' ;
[154]shortstring: '"' shortstringitem1_content
('"' / FATAL<"string not terminated before input end">) /
['] shortstringitem2_content
([']/ FATAL<"string not terminated before input end">);
[155]^^shortstringitem1_content:
(!'"' shortstringitem)*;
[156]^^shortstringitem2_content:
(!['] shortstringitem)*;
longstring: '"""' longstring1_content
('"""' / FATAL<"triple quoted string not terminated">)
/ ['][']['] longstring2_content
(['][']['] / FATAL<"triple quoted string not terminated">);
[157]^^longstring1_content: (!'"""' longstringitem)* ;
[158]^^longstring2_content: (!(['][']['])longstringitem)* ;
[159]shortstringitem: escapeseq
/ '\\' NL
/ '\\' check_unrecognized_escape .
/ [^\n]
/ FATAL<"new line in string not allowed">;
[160]longstringitem: escapeseq / '\\' check_unrecognized_escape . / . ;
[161]check_unrecognized_escape:
!in_raw_ WARNING<"unrecognized escape"> / &.;
[162]escapeseq: in_raw_ '\\' ( unicode_4digits / unicode_8digits )
/ !in_raw_ '\\'
( [\\'"abfnrtv]
/ 'N{' NAME '}'
/ unicode_4digits
/ unicode_8digits
/ [0-8]{1,3}
/ hex_2digits );
[163]^^unicode_4digits: 'u'([0-9A-Fa-f]{4}/WARNING<"u must be followed by 4 hex digits">);
[164]^^unicode_8digits: 'U'([0-9A-Fa-f]{8}/WARNING<"U must be followed by 8 hex digits">);
[165]^^hex_2digits: 'x'([0-9A-Fa-f]{2} /WARNING<"x must be followed by 2 hex digits">);
set_explicit_line_joining_:;
<</Grammar>>
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