mw.visitJumpInsn(GOTO, end);
mw.visitLabel(isString);
mw.visitMethodInsn(INVOKESTATIC, NAME, "o2s",
"(Ljava/lang/Object;)Ljava/lang/String;");
second.parseString(mw, local, variableNames);
checkString(mw, exp1IsNumber);
mw.visitLabel(end);
} else {
// if (弱类型(exp1) && 弱类型(exp2) instanceof