Named parameter
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In computing, naming of parameters (or named parameters) means that the method signature clearly states the name (meaning) of each parameter. This is not used in languages like Java and C++. It is supported in languages like Smalltalk and Objective-C.
For example, here is a Java method call:
window.addNewControl("Title", 20, 50, 100, 50, true);
Here is the same method call in ObjC:
[window addNewControlWithTitle:@"Title"
xPosition:20
yPosition:50
width:100
height:50
drawingNow:YES];
The Objective-C version is easier to read as each parameter's meaning is more clearly stated in the method call itself. It does mean that the method call is in a way a bit messier and longer to type, but it is a lot of easier to read. Code that is easy to read is easier to maintain and fix, and those are big benefits these days when code sizes are getting huge.
Note that the named parameters in Smalltalk and Objective-C refers to the syntactical presentation and not to the underlying implementation. Neither language supports named parameters in the sense that, say, Python supports key=value style parameters.
For example, in the above Objective-C fragment, the method name is literally "addNewControlWithTitle:xPosition:yPosition:width:height:drawingNow:".