Method Evaluate

parser_expression.go:227–283

(ctx *ExecutionContext)

}

func (expr *simpleExpression) Evaluate(ctx *ExecutionContext) (*Value, *Error) {
	t1, err := expr.term1.Evaluate(ctx)
	if err != nil {
		return nil, err
	}
	result := t1

	if expr.negate {
		result = result.Negate()
	}

	if expr.negativeSign {
		if result.IsNumber() {
			switch {
			case result.IsFloat():
				result = AsValue(-1 * result.Float())
			case result.IsInteger():
				result = AsValue(-1 * result.Integer())
			default:
				return nil, ctx.Error("Operation between a number and a non-(float/integer) is not possible", nil)
			}
		} else {
			return nil, ctx.Error("Negative sign on a non-number expression", expr.GetPositionToken())
		}
	}

	if expr.term2 != nil {
		t2, err := expr.term2.Evaluate(ctx)
		if err != nil {
			return nil, err
		}
		switch expr.opToken.Val {
		case "+":
			if result.IsString() || t2.IsString() {
				// Result will be a string
				return AsValue(result.String() + t2.String()), nil
			}
			if result.IsFloat() || t2.IsFloat() {
				// Result will be a float
				return AsValue(result.Float() + t2.Float()), nil
			}
			// Result will be an integer
			return AsValue(result.Integer() + t2.Integer()), nil
		case "-":
			if result.IsFloat() || t2.IsFloat() {
				// Result will be a float
				return AsValue(result.Float() - t2.Float()), nil
			}
			// Result will be an integer
			return AsValue(result.Integer() - t2.Integer()), nil
		default:
			return nil, ctx.Error("Unimplemented", expr.GetPositionToken())
		}
	}

	return result, nil
}