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-rw-r--r--doc/classes/Callable.xml69
1 files changed, 51 insertions, 18 deletions
diff --git a/doc/classes/Callable.xml b/doc/classes/Callable.xml
index dd48ee6790..50be9b86bf 100644
--- a/doc/classes/Callable.xml
+++ b/doc/classes/Callable.xml
@@ -1,10 +1,10 @@
<?xml version="1.0" encoding="UTF-8" ?>
<class name="Callable" version="4.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../class.xsd">
<brief_description>
- An object representing a method in a certain object that can be called.
+ Built-in type representing a method in an object instance or a standalone function.
</brief_description>
<description>
- [Callable] is a first class object which can be held in variables and passed to functions. It represents a given method in an [Object], and is typically used for signal callbacks.
+ [Callable] is a built-in [Variant] type that represents a function. It can either be a method within an [Object] instance, or a standalone function not related to any object, like a lambda function. Like all [Variant] types, it can be stored in variables and passed to other functions. It is most commonly used for signal callbacks.
[b]Example:[/b]
[codeblocks]
[gdscript]
@@ -14,24 +14,38 @@
func test():
var callable = Callable(self, "print_args")
callable.call("hello", "world") # Prints "hello world ".
- callable.call(Vector2.UP, 42, callable) # Prints "(0, -1) 42 Node(Node.gd)::print_args".
+ callable.call(Vector2.UP, 42, callable) # Prints "(0, -1) 42 Node(node.gd)::print_args".
callable.call("invalid") # Invalid call, should have at least 2 arguments.
[/gdscript]
[csharp]
- public void PrintArgs(object arg1, object arg2, object arg3 = null)
+ // Default parameter values are not supported.
+ public void PrintArgs(Variant arg1, Variant arg2, Variant arg3 = default)
{
GD.PrintS(arg1, arg2, arg3);
}
public void Test()
{
- Callable callable = new Callable(this, nameof(PrintArgs));
- callable.Call("hello", "world"); // Prints "hello world null".
+ // Invalid calls fail silently.
+ Callable callable = new Callable(this, MethodName.PrintArgs);
+ callable.Call("hello", "world"); // Default parameter values are not supported, should have 3 arguments.
callable.Call(Vector2.Up, 42, callable); // Prints "(0, -1) 42 Node(Node.cs)::PrintArgs".
- callable.Call("invalid"); // Invalid call, should have at least 2 arguments.
+ callable.Call("invalid"); // Invalid call, should have 3 arguments.
}
[/csharp]
[/codeblocks]
+ In GDScript, it's possible to create lambda functions within a method. Lambda functions are custom callables that are not associated with an [Object] instance. Optionally, lambda functions can also be named. The name will be displayed in the debugger, or when calling [method get_method].
+ [codeblock]
+ func _init():
+ var my_lambda = func (message):
+ print(message)
+
+ # Prints Hello everyone!
+ my_lambda.call("Hello everyone!")
+
+ # Prints "Attack!", when the button_pressed signal is emitted.
+ button_pressed.connect(func(): print("Attack!"))
+ [/codeblock]
</description>
<tutorials>
</tutorials>
@@ -39,7 +53,7 @@
<constructor name="Callable">
<return type="Callable" />
<description>
- Constructs a null [Callable] with no object nor method bound.
+ Constructs an empty [Callable], with no object nor method bound.
</description>
</constructor>
<constructor name="Callable">
@@ -54,7 +68,7 @@
<param index="0" name="object" type="Object" />
<param index="1" name="method" type="StringName" />
<description>
- Creates a new [Callable] for the method called [param method] in the specified [param object].
+ Creates a new [Callable] for the method named [param method] in the specified [param object].
</description>
</constructor>
</constructors>
@@ -62,7 +76,14 @@
<method name="bind" qualifiers="vararg const">
<return type="Callable" />
<description>
- Returns a copy of this [Callable] with the arguments bound. Bound arguments are passed after the arguments supplied by [method call].
+ Returns a copy of this [Callable] with one or more arguments bound. When called, the bound arguments are passed [i]after[/i] the arguments supplied by [method call].
+ </description>
+ </method>
+ <method name="bindv">
+ <return type="Callable" />
+ <param index="0" name="arguments" type="Array" />
+ <description>
+ Returns a copy of this [Callable] with one or more arguments bound, reading them from an array. When called, the bound arguments are passed [i]after[/i] the arguments supplied by [method call].
</description>
</method>
<method name="call" qualifiers="vararg const">
@@ -85,13 +106,25 @@
<return type="Variant" />
<param index="0" name="arguments" type="Array" />
<description>
- Calls the method represented by this [Callable]. Contrary to [method call], this method does not take a variable number of arguments but expects all arguments to be passed via a single [Array].
+ Calls the method represented by this [Callable]. Unlike [method call], this method expects all arguments to be contained inside the [param arguments] [Array].
+ </description>
+ </method>
+ <method name="get_bound_arguments" qualifiers="const">
+ <return type="Array" />
+ <description>
+ Return the bound arguments (as long as [method get_bound_arguments_count] is greater than zero), or empty (if [method get_bound_arguments_count] is less than or equal to zero).
+ </description>
+ </method>
+ <method name="get_bound_arguments_count" qualifiers="const">
+ <return type="int" />
+ <description>
+ Returns the total amount of arguments bound (or unbound) via successive [method bind] or [method unbind] calls. If the amount of arguments unbound is greater than the ones bound, this function returns a value less than zero.
</description>
</method>
<method name="get_method" qualifiers="const">
<return type="StringName" />
<description>
- Returns the name of the method represented by this [Callable].
+ Returns the name of the method represented by this [Callable]. If the callable is a lambda function, returns the function's name.
</description>
</method>
<method name="get_object" qualifiers="const">
@@ -116,7 +149,7 @@
<method name="is_custom" qualifiers="const">
<return type="bool" />
<description>
- Returns [code]true[/code] if this [Callable] is a custom callable whose behavior differs based on implementation details. Custom callables are used in the engine for various reasons. If [code]true[/code], you can't use [method get_method].
+ Returns [code]true[/code] if this [Callable] is a custom callable. Custom callables are created from [method bind] or [method unbind]. In GDScript, lambda functions are also custom callables.
</description>
</method>
<method name="is_null" qualifiers="const">
@@ -128,33 +161,33 @@
<method name="is_standard" qualifiers="const">
<return type="bool" />
<description>
- Returns [code]true[/code] if this [Callable] is a standard callable, referencing an object and a method using a [StringName].
+ Returns [code]true[/code] if this [Callable] is a standard callable. This method is the opposite of [method is_custom]. Returns [code]false[/code] if this callable is a lambda function.
</description>
</method>
<method name="is_valid" qualifiers="const">
<return type="bool" />
<description>
- Returns [code]true[/code] if the object exists and has a valid function assigned, or is a custom callable.
+ Returns [code]true[/code] if the callable's object exists and has a valid method name assigned, or is a custom callable.
</description>
</method>
<method name="rpc" qualifiers="vararg const">
<return type="void" />
<description>
- Perform an RPC (Remote Procedure Call). This is used for multiplayer and is normally not available unless the function being called has been marked as [i]RPC[/i]. Calling it on unsupported functions will result in an error.
+ Perform an RPC (Remote Procedure Call). This is used for multiplayer and is normally not available, unless the function being called has been marked as [i]RPC[/i]. Calling this method on unsupported functions will result in an error. See [method Node.rpc].
</description>
</method>
<method name="rpc_id" qualifiers="vararg const">
<return type="void" />
<param index="0" name="peer_id" type="int" />
<description>
- Perform an RPC (Remote Procedure Call) on a specific peer ID (see multiplayer documentation for reference). This is used for multiplayer and is normally not available unless the function being called has been marked as [i]RPC[/i]. Calling it on unsupported functions will result in an error.
+ Perform an RPC (Remote Procedure Call) on a specific peer ID (see multiplayer documentation for reference). This is used for multiplayer and is normally not available unless the function being called has been marked as [i]RPC[/i]. Calling this method on unsupported functions will result in an error. See [method Node.rpc_id].
</description>
</method>
<method name="unbind" qualifiers="const">
<return type="Callable" />
<param index="0" name="argcount" type="int" />
<description>
- Returns a copy of this [Callable] with the arguments unbound. Calling the returned [Callable] will call the method without the extra arguments that are supplied in the [Callable] on which you are calling this method.
+ Returns a copy of this [Callable] with the arguments unbound, as defined by [param argcount]. Calling the returned [Callable] will call the method without the extra arguments that are supplied in the [Callable] on which you are calling this method.
</description>
</method>
</methods>
generated by cgit v1.2.3 (git 2.25.1) at 2025-03-06 09:50:34 +0000