Expecting token of type 'XX' but found `XX'

[zrwsmd]

[msujew]

@zrwsmd the token ID shadows Identifier, since it matches almost the same content, but comes before it in the terminal listing. Terminals are matched on a first-fit basis. Generally, different terminals should not intersect.

[zrwsmd]

so if i need to match both INT qw_3 qw3 aa this four character string,how should i define a Terminals ,just can not write it correctly

grammar StructuredText

entry Document:
(stStatements+=Var);

Var:
'VAR' name=Identifier ':' type=Identifier ';' 'END_VAR'
;

// identifier characters
terminal fragment Underscore: /_/;
terminal fragment Letters: /[a-zA-Z]+/;
terminal fragment Digits: /[0-9]+/;
terminal Identifier: ((Underscore)? ((Digits) | Letters));

// hidden
hidden terminal WS: /\s+/;
hidden terminal ML_COMMENT: //*[\s\S]?*//;
hidden terminal ML_COMMENT_ST: /(*[\s\S]?*)/;
hidden terminal SL_COMMENT: ///[^\n\r]*/;

[msujew]

You can just use a simple regex terminal for that like terminal ID: /[a-zA-Z][\w]*/.