Parser - yacc(1)


Takes the tokens/etc. from lex(1) and validates everything using the grammar of the language. As well as building an AST representation of the statements, etc.

 %union {  -- yacc's value stack used to pass data inside parser
   symbol table pointer
   char name[...]
   int yyint
   value (data struct for constants)
   ast - syntax tree for expressions etc.
 }