class Expression
package godot
extends Reference › Object
@:nativeGen@:build(godot.Godot.buildUserClass())@:autoBuild(godot.Godot.buildUserClass())@:build(godot.Godot.buildUserClass())@:autoBuild(godot.Godot.buildUserClass())@:libType@:csNative@:native("Godot.Expression")@:autoBuild(godot.Godot.buildUserClass())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 godot.LineEdit node to write our expression and show the result.
onready var expression = Expression.new()
func _ready():
$LineEdit.connect("text_entered", self, "_on_text_entered")
func _on_text_entered(command):
var error = expression.parse(command, [])
if error != OK:
print(expression.get_error_text())
return
var result = expression.execute([], null, true)
if not expression.has_execute_failed():
$LineEdit.text = str(result)
Constructor
Methods
@:native("Execute")execute(?inputs:Array, ?baseInstance:Object, ?showError:Bool):Dynamic
Executes the expression that was previously parsed by godot.Expression.parse and returns the result. Before you use the returned object, you should check if the method failed by calling godot.Expression.hasExecuteFailed.
If you defined input variables in godot.Expression.parse, you can specify their values in the inputs array, in the same order.
Parameters:
inputs | If the parameter is null, then the default value is new Godot.Collections.Array { } |
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@:native("GetErrorText")getErrorText():String
Returns the error text if godot.Expression.parse has failed.
@:native("HasExecuteFailed")hasExecuteFailed():Bool
Returns true if godot.Expression.execute has failed.
@:native("Parse")parse(expression:String, ?inputNames:Array<String>):Error
Parses the expression and returns an godot.Error code.
You can optionally specify names of variables that may appear in the expression with input_names, so that you can bind them when it gets executed.
Parameters:
inputNames | If the parameter is null, then the default value is Array.Empty<string>() |
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Inherited Variables
Defined by Object
@:native("DynamicObject")read onlydynamicObject:Dynamic
Gets a new godot.DynamicGodotObject associated with this instance.
@:native("NativeInstance")read onlynativeInstance:IntPtr
The pointer to the native instance of this godot.Object.
Inherited Methods
Defined by Reference
@:native("InitRef")initRef():Bool
Initializes the internal reference counter. Use this only if you really know what you are doing.
Returns whether the initialization was successful.
@:native("Reference_")reference_():Bool
Increments the internal reference counter. Use this only if you really know what you are doing.
Returns true if the increment was successful, false otherwise.
@:native("Unreference")unreference():Bool
Decrements the internal reference counter. Use this only if you really know what you are doing.
Returns true if the decrement was successful, false otherwise.
Defined by Object
@:native("_Get")_Get(property:String):Dynamic
Virtual method which can be overridden to customize the return value of godot.Object.get.
Returns the given property. Returns null if the property does not exist.
@:native("_GetPropertyList")_GetPropertyList():Array
Virtual method which can be overridden to customize the return value of godot.Object.getPropertyList.
Returns the object's property list as an godot.Collections_Array of dictionaries.
Each property's godot.Collections_Dictionary must contain at least name: String and type: int (see godot.Variant_Type) entries. Optionally, it can also include hint: int (see godot.PropertyHint), hint_string: String, and usage: int (see godot.PropertyUsageFlags).
@:native("_Notification")_Notification(what:Int):Void
Called whenever the object receives a notification, which is identified in what by a constant. The base godot.Object has two constants godot.Object.notificationPostinitialize and godot.Object.notificationPredelete, but subclasses such as godot.Node define a lot more notifications which are also received by this method.
@:native("_Set")_Set(property:String, value:Dynamic):Bool
Virtual method which can be overridden to customize the return value of godot.Object.set.
Sets a property. Returns true if the property exists.
@:native("AddUserSignal")addUserSignal(signal:String, ?arguments:Array):Void
Adds a user-defined signal. Arguments are optional, but can be added as an godot.Collections_Array of dictionaries, each containing name: String and type: int (see godot.Variant_Type) entries.
Parameters:
arguments | If the parameter is null, then the default value is new Godot.Collections.Array { } |
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@:native("Call")call(method:String, args:HaxeArray<Dynamic>):Dynamic
Calls the method on the object and returns the result. This method supports a variable number of arguments, so parameters are passed as a comma separated list. Example:
call("set", "position", Vector2(42.0, 0.0))
Note: In C#, the method name must be specified as snake_case if it is defined by a built-in Godot node. This doesn't apply to user-defined methods where you should use the same convention as in the C# source (typically PascalCase).
@:native("CallDeferred")callDeferred(method:String, args:HaxeArray<Dynamic>):Void
Calls the method on the object during idle time. This method supports a variable number of arguments, so parameters are passed as a comma separated list. Example:
call_deferred("set", "position", Vector2(42.0, 0.0))
Note: In C#, the method name must be specified as snake_case if it is defined by a built-in Godot node. This doesn't apply to user-defined methods where you should use the same convention as in the C# source (typically PascalCase).
@:native("Callv")callv(method:String, argArray:Array):Dynamic
Calls the method on the object and returns the result. Contrarily to godot.Object.call, this method does not support a variable number of arguments but expects all parameters to be via a single godot.Collections_Array.
callv("set", [ "position", Vector2(42.0, 0.0) ])
@:native("CanTranslateMessages")canTranslateMessages():Bool
Returns true if the object can translate strings. See godot.Object.setMessageTranslation and godot.Object.tr.
@:native("Connect")connect(signal:String, target:Object, method:String, ?binds:Array, ?flags:UInt):Error
Connects a signal to a method on a target object. Pass optional binds to the call as an godot.Collections_Array of parameters. These parameters will be passed to the method after any parameter used in the call to godot.Object.emitSignal. Use flags to set deferred or one-shot connections. See godot.Object_ConnectFlags constants.
A signal can only be connected once to a method. It will print an error if already connected, unless the signal was connected with godot.Object_ConnectFlags.referenceCounted. To avoid this, first, use godot.Object.isConnected to check for existing connections.
If the target is destroyed in the game's lifecycle, the connection will be lost.
Examples:
connect("pressed", self, "_on_Button_pressed") # BaseButton signal
connect("text_entered", self, "_on_LineEdit_text_entered") # LineEdit signal
connect("hit", self, "_on_Player_hit", [ weapon_type, damage ]) # User-defined signal
An example of the relationship between binds passed to godot.Object.connect and parameters used when calling godot.Object.emitSignal:
connect("hit", self, "_on_Player_hit", [ weapon_type, damage ]) # weapon_type and damage are passed last
emit_signal("hit", "Dark lord", 5) # "Dark lord" and 5 are passed first
func _on_Player_hit(hit_by, level, weapon_type, damage):
print("Hit by %s (lvl %d) with weapon %s for %d damage" % [hit_by, level, weapon_type, damage])
Parameters:
binds | If the parameter is null, then the default value is new Godot.Collections.Array { } |
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@:native("Disconnect")disconnect(signal:String, target:Object, method:String):Void
Disconnects a signal from a method on the given target.
If you try to disconnect a connection that does not exist, the method will print an error. Use godot.Object.isConnected to ensure that the connection exists.
@:native("Dispose")dispose():Void
@:native("Dispose")@:protectedDispose(disposing:Bool):Void
Disposes of this godot.Object.
@:native("EmitSignal")emitSignal(signal:String, args:HaxeArray<Dynamic>):Void
Emits the given signal. The signal must exist, so it should be a built-in signal of this class or one of its parent classes, or a user-defined signal. This method supports a variable number of arguments, so parameters are passed as a comma separated list. Example:
emit_signal("hit", weapon_type, damage)
emit_signal("game_over")
@:native("Free")free():Void
Deletes the object from memory immediately. For godot.Nodes, you may want to use godot.Node.queueFree to queue the node for safe deletion at the end of the current frame.
Important: If you have a variable pointing to an object, it will not be assigned to null once the object is freed. Instead, it will point to a previously freed instance and you should validate it with @GDScript.is_instance_valid before attempting to call its methods or access its properties.
@:native("Get")get(property:String):Dynamic
Returns the Variant value of the given property. If the property doesn't exist, this will return null.
Note: In C#, the property name must be specified as snake_case if it is defined by a built-in Godot node. This doesn't apply to user-defined properties where you should use the same convention as in the C# source (typically PascalCase).
@:native("GetClass")getClass():String
Returns the object's class as a String. See also godot.Object.isClass.
Note: godot.Object.getClass does not take class_name declarations into account. If the object has a class_name defined, the base class name will be returned instead.
@:native("GetIncomingConnections")getIncomingConnections():Array
Returns an godot.Collections_Array of dictionaries with information about signals that are connected to the object.
Each godot.Collections_Dictionary contains three String entries:
-
sourceis a reference to the signal emitter. -
signal_nameis the name of the connected signal. -
method_nameis the name of the method to which the signal is connected.
@:native("GetIndexed")getIndexed(property:NodePath):Dynamic
Gets the object's property indexed by the given godot.NodePath. The node path should be relative to the current object and can use the colon character (:) to access nested properties. Examples: "position:x" or "material:next_pass:blend_mode".
Note: Even though the method takes godot.NodePath argument, it doesn't support actual paths to godot.Nodes in the scene tree, only colon-separated sub-property paths. For the purpose of nodes, use godot.Node.getNodeAndResource instead.
@:native("GetInstanceId")getInstanceId():UInt64
Returns the object's unique instance ID.
This ID can be saved in godot.EncodedObjectAsID, and can be used to retrieve the object instance with @GDScript.instance_from_id.
@:native("GetMeta")getMeta(name:String):Dynamic
Returns the object's metadata entry for the given name.
@:native("GetMethodList")getMethodList():Array
Returns the object's methods and their signatures as an godot.Collections_Array.
@:native("GetPropertyList")getPropertyList():Array
Returns the object's property list as an godot.Collections_Array of dictionaries.
Each property's godot.Collections_Dictionary contain at least name: String and type: int (see godot.Variant_Type) entries. Optionally, it can also include hint: int (see godot.PropertyHint), hint_string: String, and usage: int (see godot.PropertyUsageFlags).
@:native("GetScript")getScript():Reference
Returns the object's godot.Script instance, or null if none is assigned.
@:native("GetSignalConnectionList")getSignalConnectionList(signal:String):Array
Returns an godot.Collections_Array of connections for the given signal.
@:native("GetSignalList")getSignalList():Array
Returns the list of signals as an godot.Collections_Array of dictionaries.
@:native("HasMeta")hasMeta(name:String):Bool
Returns true if a metadata entry is found with the given name.
@:native("HasMethod")hasMethod(method:String):Bool
Returns true if the object contains the given method.
@:native("HasUserSignal")hasUserSignal(signal:String):Bool
Returns true if the given user-defined signal exists. Only signals added using godot.Object.addUserSignal are taken into account.
@:native("IsBlockingSignals")isBlockingSignals():Bool
Returns true if signal emission blocking is enabled.
@:native("IsClass")isClass(class_:String):Bool
Returns true if the object inherits from the given class. See also godot.Object.getClass.
Note: godot.Object.isClass does not take class_name declarations into account. If the object has a class_name defined, godot.Object.isClass will return false for that name.
@:native("IsConnected")isConnected(signal:String, target:Object, method:String):Bool
Returns true if a connection exists for a given signal, target, and method.
@:native("IsQueuedForDeletion")isQueuedForDeletion():Bool
Returns true if the godot.Node.queueFree method was called for the object.
@:native("Notification")notification(what:Int, ?reversed:Bool):Void
Send a given notification to the object, which will also trigger a call to the godot.Object._Notification method of all classes that the object inherits from.
If reversed is true, godot.Object._Notification is called first on the object's own class, and then up to its successive parent classes. If reversed is false, godot.Object._Notification is called first on the highest ancestor (godot.Object itself), and then down to its successive inheriting classes.
@:native("PropertyListChangedNotify")propertyListChangedNotify():Void
Notify the editor that the property list has changed, so that editor plugins can take the new values into account. Does nothing on export builds.
@:native("RemoveMeta")removeMeta(name:String):Void
Removes a given entry from the object's metadata. See also godot.Object.setMeta.
@:native("Set")set(property:String, value:Dynamic):Void
Assigns a new value to the given property. If the property does not exist or the given value's type doesn't match, nothing will happen.
Note: In C#, the property name must be specified as snake_case if it is defined by a built-in Godot node. This doesn't apply to user-defined properties where you should use the same convention as in the C# source (typically PascalCase).
@:native("SetBlockSignals")setBlockSignals(enable:Bool):Void
If set to true, signal emission is blocked.
@:native("SetDeferred")setDeferred(property:String, value:Dynamic):Void
Assigns a new value to the given property, after the current frame's physics step. This is equivalent to calling godot.Object.set via godot.Object.callDeferred, i.e. call_deferred("set", property, value).
Note: In C#, the property name must be specified as snake_case if it is defined by a built-in Godot node. This doesn't apply to user-defined properties where you should use the same convention as in the C# source (typically PascalCase).
@:native("SetIndexed")setIndexed(property:NodePath, value:Dynamic):Void
Assigns a new value to the property identified by the godot.NodePath. The node path should be relative to the current object and can use the colon character (:) to access nested properties. Example:
set_indexed("position", Vector2(42, 0))
set_indexed("position:y", -10)
print(position) # (42, -10)
@:native("SetMessageTranslation")setMessageTranslation(enable:Bool):Void
Defines whether the object can translate strings (with calls to godot.Object.tr). Enabled by default.
@:native("SetMeta")setMeta(name:String, value:Dynamic):Void
Adds, changes or removes a given entry in the object's metadata. Metadata are serialized and can take any Variant value.
To remove a given entry from the object's metadata, use godot.Object.removeMeta. Metadata is also removed if its value is set to null. This means you can also use set_meta("name", null) to remove metadata for "name".
@:native("SetScript")setScript(script:Reference):Void
Assigns a script to the object. Each object can have a single script assigned to it, which are used to extend its functionality.
If the object already had a script, the previous script instance will be freed and its variables and state will be lost. The new script's method will be called.
@:native("ToSignal")toSignal(source:Object, signal:String):SignalAwaiter
Returns a new godot.SignalAwaiter awaiter configured to complete when the instance
source emits the signal specified by the signal parameter.
Parameters:
source | The instance the awaiter will be listening to. |
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signal | The signal the awaiter will be waiting for. This sample prints a message once every frame up to 100 times. |
Returns:
A godot.SignalAwaiter that completes when
source emits the signal.
@:native("ToString")toString():String
@:native("Tr")tr(message:String):String
Translates a message using translation catalogs configured in the Project Settings.
Only works if message translation is enabled (which it is by default), otherwise it returns the message unchanged. See godot.Object.setMessageTranslation.