Edit

Pipe First

Pipe first is the operator to apply a function to a value where data is passed as the first argument. -> is a convenient operator that allows you to "flip" your code inside-out. a(b) becomes b->a.

let result = value->function;

Imagine you have the following:

validateAge(getAge(parseData(person)))

This is slightly hard to read, since you need to read the code from the innermost part, to the outer parts. Use Pipe First to streamline it

person
  ->parseData
  ->getAge
  ->validateAge

Basically, parseData(person) is transformed into person->parseData, and getAge(person->parseData) is transformed into person->parseData->getAge, etc.

This works when the function takes more than one argument too.

a(one, two, three)

is the same as

one->a(two, three)

This works with labeled arguments too.

This section is documented under Melange's documentation as well: Pipe first.

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