Question

Is there any way to force operator precedence in Scala like you do in Haskell with $?

For example, in Haskell, you have:

a b c = ((a b) c)

and

a $ b c = a (b c)

Is there a similar way to do this in Scala? I know Scala doesn’t have operators per se, but is there a way to achieve a similar effect?

Answer 1

infix vs . notation is often used in a similar fashion to control precedence:

a b c d == a.b(c).d
a.b c d == a.b.c(d)
a b c.d == a.b(c.d)

Scala also has a fixed precedence ordering for operators used in infix notation:

(all letters)
|
^
&
< >
= !
:
+ -
* / %
(all other special characters)

Names can usually chosen explicitly to take advantage of this. For example, ~ and ^^ in the standard parsers library.