set.java

用java实现的编译器. 包括语法分析

package inter;
import lexer.*;
import symbols.*;
public class Set extends Stmt {
	public Id id;
	public Expr expr;
	public Set(Id i, Expr x) {
		id = i;
		expr =x;
		if(check(id.type, expr.type) == null)
			error("type error");
	}
	public Type check(Type p1, Type p2) {
		if(Type.numeric(p1) && Type.numeric(p2))
			return p2;	
		else if(p1 == Type.Bool && p2 == Type.Bool)				return p2;
		else return null;
	}
	public void gen(int b, int a) {
		emit( id.toString() + " = " + expr.gen().toString() );

	}
}