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Expression¶
Inherits: RefCounted < Object
A class that stores an expression you can execute.
Description¶
An expression can be made of any arithmetic operation, built-in math function call, method call of a passed instance, or built-in type construction call.
An example expression text using the built-in math functions could be sqrt(pow(3, 2) + pow(4, 2)).
In the following example we use a LineEdit node to write our expression and show the result.
var expression = Expression.new()
func _ready():
$LineEdit.text_submitted.connect(self._on_text_submitted)
func _on_text_submitted(command):
var error = expression.parse(command)
if error != OK:
print(expression.get_error_text())
return
var result = expression.execute()
if not expression.has_execute_failed():
$LineEdit.text = str(result)
private Expression _expression = new Expression();
public override void _Ready()
{
GetNode<LineEdit>("LineEdit").TextSubmitted += OnTextEntered;
}
private void OnTextEntered(string command)
{
Error error = _expression.Parse(command);
if (error != Error.Ok)
{
GD.Print(_expression.GetErrorText());
return;
}
Variant result = _expression.Execute();
if (!_expression.HasExecuteFailed())
{
GetNode<LineEdit>("LineEdit").Text = result.ToString();
}
}