Proposal: ArgumentDo

C Maeder chr.maeder at
Sat Jul 9 07:09:17 UTC 2016

The asymmetry that you mention is already apparent for (Haskell98) infix
expressions, i.e. when "composing" lambda- or if-expression:

 (if c then f else g) . \ x -> h x

Parentheses around the last argument of "." do not matter, but
parentheses around the first argument make a real difference (that the
type checker will not detect)!

Cheers Christian

Am 08.07.2016 um 14:00 schrieb Henrik Nilsson:
> Hi all,


> As a final point, the inherent asymmetry of the proposal (the
> last argument position is special as, for certain kinds of
> expressions, parentheses may be omitted there but not elsewhere)
> is also deeply unsettling.
> Best,
> /Henrik

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