Function Composition

Jed Wesley-Smith jed at
Tue Jan 1 15:40:26 PST 2013

hello lambdarians!

Just noticed that the java.util.function.Function.compose method is
round the wrong way (according to the common definition of function

The current lambda definition:

has f.compose(g) mean apply f and then apply g, whereas the usual
(most other languages and the literature) has f ∘ g mean apply g and
then apply f.

The form that Function has currently is commonly known as andThen. So,
you could rename the current method andThen and add a new compose
method that works in the usual manner.


* references:

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