xmllang.g4

grammar xmllang;

tale : function_declaration+;

FOR             : 'for each';
IF              : 'if';
IN              : 'in';
TAG             : 'node';
ELSE            : 'else';
ATTR            : 'attr';
NAME            : 'name';
TEXT            : 'text';
NODES           : 'nodes';
ATTRS           : 'attrs';
GEN             : 'generate';
PRINT           : 'print';
VALUE           : 'value';
PARSE           : 'parse';
ARRAY           : 'array';
SWITCH          : 'switch';
CASE            : 'case';
DEFAULT         : 'default';
PRIMITIVE       : 'int' | 'string';

AT              : '@';
ID              : [a-z_]+;
FILENAME        : [a-zA-Z|~.]+;
STRING          : '"' (.)*? '"';
NEWLINE         : '\r'? '\n';
ASSIGN          : '=';
EQ              : '==';
NOT             : '!=';
APPEND_ATTR     : 'adds attr';
APPEND_CHILD    : 'adds child';
REMOVE_ATTR     : 'removes attr';
REMOVE_CHILD    : 'removes child';
ROOT            : '!';
INT             : [0-9]+;
QT              : '"';
COLON           : ':';
OPEN_BRACKET    : '(';
CLOSE_BRACKET   : ')';
SPACE           : ' ' | '\t';
COMMA           : ',';
DOT             : '.';
OPEN_BLOCK      : '{';
CLOSE_BLOCK     : '}';

primitive_value       : INT | STRING | access_info;
function_declaration  : function_decl statement+ end empty_stat*;
empty_stat            : NEWLINE | SPACE ;
statement             : 
    SPACE* TAG SPACE ID OPEN_BRACKET STRING CLOSE_BRACKET NEWLINE                       # tag_assignment
  | SPACE* ATTR SPACE ID OPEN_BRACKET STRING COMMA SPACE STRING CLOSE_BRACKET NEWLINE   # attr_assignment
  | SPACE* PRIMITIVE SPACE ID SPACE ASSIGN SPACE primitive_value                        # primitive_assignment
  | SPACE* GEN OPEN_BRACKET ID COMMA SPACE STRING CLOSE_BRACKET NEWLINE                 # gen_file
  | SPACE* PARSE OPEN_BRACKET ID COMMA SPACE STRING CLOSE_BRACKET NEWLINE               # parse_file
  | SPACE* ID SPACE ASSIGN SPACE STRING NEWLINE                                         # add_text
  | SPACE* ID SPACE APPEND_CHILD SPACE ID NEWLINE                                       # append_tag
  | SPACE* ID SPACE APPEND_ATTR SPACE ID NEWLINE                                        # append_atr
  | SPACE* ID SPACE REMOVE_CHILD SPACE ID NEWLINE                                       # remove_tag
  | SPACE* ID SPACE REMOVE_ATTR SPACE ID NEWLINE                                        # remove_atr
  | SPACE* ARRAY SPACE ID NEWLINE                                                       # declare_array
  | begin_for statement+ end                                                            # for_cycle
  | ID OPEN_BRACKET (function_call_arg (COMMA SPACE function_call_arg)*)* CLOSE_BRACKET NEWLINE # function_call
  | begin_if statement+ (else_thing statement+)? end                                    # if_declaration
  | SPACE* access_info SPACE ASSIGN SPACE STRING NEWLINE                                # assign_new_value
  | print_statement                                                                     # print
  | empty_stat                                                                          # estat;

access_info:
    ID DOT NAME     # access_name
  | ID DOT TEXT     # access_text
  | ID DOT VALUE    # access_value;

value:
  ID                  
  | STRING            
  | INT;

case_block:
  NEWLINE (CASE SPACE value | DEFAULT) COLON NEWLINE statement+;

print_statement   : PRINT SPACE primitive_value NEWLINE;

begin_for         : SPACE* FOR SPACE ID SPACE IN SPACE ID SPACE OPEN_BLOCK NEWLINE;
end               : SPACE* CLOSE_BLOCK NEWLINE;
datatype          : TAG | ATTR | ARRAY | PRIMITIVE;
function_decl     : SPACE* ID OPEN_BRACKET function_args CLOSE_BRACKET SPACE OPEN_BLOCK NEWLINE;
id                : ID;
function_args     : empty_stat? | datatype SPACE id (COMMA SPACE datatype SPACE id)* ;
function_call_arg : primitive_value | ID;
begin_if          : IF SPACE comparison SPACE OPEN_BLOCK NEWLINE;
comparison        : access_info SPACE (EQ|NOT) SPACE STRING;
else_thing        : CLOSE_BLOCK SPACE ELSE SPACE OPEN_BLOCK NEWLINE;
switch_stat       : SPACE* SWITCH SPACE ID SPACE OPEN_BLOCK case_block+ CLOSE_BLOCK;