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iOS Swift Basics (retired) Collections What is an Array?

John Wu
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John Wu
Courses Plus Student 3,288 Points
Posted by John Wu
John Wu
Courses Plus Student 3,288 Points

+= operator for Array is not a syntax

Amit said the todo += ["Pickup Laundry"] is a syntax, on which I don't agree with him.

When we say the word syntax, it should be something that came with the nature of the language. Let's say defining variables using var is a syntax.

I think += is not a syntax, but a result of Operator Overloading in Swift, which internally use the .append method on Array instances.

2 Answers

Ryan Field
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Ryan Field
Courses Plus Student 21,242 Points
Ryan Field
Ryan Field
Courses Plus Student 21,242 Points

In programming, when we talk about any aspect of how a specific language works, we refer to it as 'syntax'. You could say that "+=" is the correct syntax for adding onto a string in JavaScript, but in PHP, ".=" is the proper syntax.

Parker Skiba
Parker Skiba
5,583 Points
Parker Skiba
Parker Skiba
5,583 Points

"In computer science, the syntax of a computer language is the set of rules that defines the combinations of symbols that are considered to be a correctly structured document or fragment in that language."

Thats one definition, there are others all similar. I believe that "+=" or the "Augmented assignment" operator is correctly referred to as part of the language syntax.

Parker Skiba
Parker Skiba
5,583 Points

Furthermore, operator overloading is a separate concept in and of itself to augmentation or the ".apend" method you referred to. Conceptually, in general when you overload a function, it means that you may use the same function name with different paramaters as long as they are defined in order to get different functionality.

For example if I had a function that had an overload defined I could call it like this:

callThisFunction(fiveTimes)

and:

callThisFunction(fiveTimes, atThisTime)

If you read the page you linked to it actually explained it very well..

"Typically, you’ll use overloading to extend an operation to a new object while maintaining the original semantics, rather than defining different (and confusing) behavior."