Converting from Antlr3 to Antlr4

匆匆过客 提交于 2019-12-12 06:32:44
问题 I am in the process of converting an antlr3 to antlr4 grammar. I have stripped out all the syntactic predicates. I am struggling to make a correct conversion of this relaxed_date_month_first : relaxed_day_of_week? relaxed_month COMMA? WHITE_SPACE relaxed_day_of_month (relaxed_year_prefix relaxed_year)? -> ^(EXPLICIT_DATE relaxed_day_of_month relaxed_month relaxed_day_of_week? relaxed_year?) to antlr4 grammar. Everytime the antlr4 tool runs into "->" character it says "extraneous input '->'