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This makes it easier to spot syntax errors when editing the class reference. The schema is referenced locally so validation can still work offline. Each class XML's schema conformance is also checked on GitHub Actions.
87 lines
3.2 KiB
XML
87 lines
3.2 KiB
XML
<?xml version="1.0" encoding="UTF-8" ?>
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<class name="Expression" inherits="RefCounted" version="4.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../class.xsd">
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<brief_description>
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A class that stores an expression you can execute.
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</brief_description>
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<description>
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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.
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An example expression text using the built-in math functions could be [code]sqrt(pow(3, 2) + pow(4, 2))[/code].
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In the following example we use a [LineEdit] node to write our expression and show the result.
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[codeblocks]
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[gdscript]
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var expression = Expression.new()
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func _ready():
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$LineEdit.connect("text_submitted", self, "_on_text_submitted")
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func _on_text_submitted(command):
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var error = expression.parse(command)
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if error != OK:
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print(expression.get_error_text())
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return
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var result = expression.execute()
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if not expression.has_execute_failed():
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$LineEdit.text = str(result)
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[/gdscript]
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[csharp]
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public Expression expression = new Expression();
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public override void _Ready()
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{
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GetNode("LineEdit").Connect("text_submitted", this, nameof(OnTextEntered));
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}
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private void OnTextEntered(string command)
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{
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Error error = expression.Parse(command);
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if (error != Error.Ok)
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{
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GD.Print(expression.GetErrorText());
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return;
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}
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object result = expression.Execute();
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if (!expression.HasExecuteFailed())
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{
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GetNode<LineEdit>("LineEdit").Text = result.ToString();
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}
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}
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[/csharp]
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[/codeblocks]
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</description>
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<tutorials>
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</tutorials>
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<methods>
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<method name="execute">
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<return type="Variant" />
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<argument index="0" name="inputs" type="Array" default="[]" />
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<argument index="1" name="base_instance" type="Object" default="null" />
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<argument index="2" name="show_error" type="bool" default="true" />
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<description>
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Executes the expression that was previously parsed by [method parse] and returns the result. Before you use the returned object, you should check if the method failed by calling [method has_execute_failed].
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If you defined input variables in [method parse], you can specify their values in the inputs array, in the same order.
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</description>
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</method>
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<method name="get_error_text" qualifiers="const">
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<return type="String" />
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<description>
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Returns the error text if [method parse] has failed.
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</description>
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</method>
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<method name="has_execute_failed" qualifiers="const">
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<return type="bool" />
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<description>
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Returns [code]true[/code] if [method execute] has failed.
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</description>
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</method>
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<method name="parse">
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<return type="int" enum="Error" />
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<argument index="0" name="expression" type="String" />
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<argument index="1" name="input_names" type="PackedStringArray" default="PackedStringArray()" />
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<description>
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Parses the expression and returns an [enum Error] code.
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You can optionally specify names of variables that may appear in the expression with [code]input_names[/code], so that you can bind them when it gets executed.
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</description>
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</method>
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</methods>
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</class>
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