Haskell IF statements -

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i'm pretty new haskell, if make if statement:

function b c      | (a+b == 0) = true      | --etc.      | otherwise = false

is second if statement same else if in other languages, or if. assume former can have 1 output, want make sure.

the construct used called guard. haskell checks given alternatives 1 after until 1 condition yields true. evaluates right hand side of equation.

you pretty write

function n     | n == 1 = ...    | n == 2 = ...    | n >= 3 = ...

thus guard kinds of represents if/elseif construct other languages. otherwise defined true, last

| otherwise =

will true , therefore represents catch-all else clause.

nontheless, haskell has usual a = if foo 23 else 42 statement.


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