are patterns synonyms definable in GHCI?

Dr. ERDI Gergo gergo at
Thu Dec 18 10:51:49 UTC 2014

On Thu, 18 Dec 2014, Carter Schonwald wrote:

> Hey all,I was trying to define some pattern synonyms in ghci recently, and that doesnt
> seem to work. Is that something slated to be fix in 7.10 or something?

I thought GHCi accepts things that would be valid in a 'do' section? So 

x = ()

doesn't work in GHCi, but

let x = ()


Pattern synonyms don't work for the exact same reason: they are not valid 
inside a 'do' block.

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