// ReturnStatement ::= 'return' Expressionopt ';'
// return pushs a position on this.intStack in case there is no expression
if (this.expressionLengthStack[this.expressionLengthPtr--] != 0) {
pushOnAstStack(
new ReturnStatement(
this.expressionStack[this.expressionPtr--],
this.intStack[this.intPtr--],
this.endStatementPosition)
);
} else {
pushOnAstStack(new ReturnStatement(null, this.intStack[this.intPtr--], this.endStatementPosition));
}
}