15_DifferencesFromPurescript.md

Main differences between Hamler and Purecript

Hamler added syntaxes which are more familiar to Erlang programmers.

Binary

Hamler support Binary

getA :: Binary -> Maybe Integer
getA << a:24:Big-Integer , b:4:Binary-Little , c:3:Binary >> = Just a
getA _                                                       = Nothing

Map

Map in Hamler is more similar to Erlang

getID :: Map String Integer -> Maybe Integer
getID #{ "Wang":= x, "Thomas" := y, "Leeming" := z } = Just x
getID _                                              = Nothing

Atom

We have atoms and allow pattern match on atom. It is now one of the primitive type in Hamler.

:hello
:world
:hello_World123

String

In PureScript, String is one of the primitive type. However, in Hamler String is [Char] a list of Chars.

Tuple

Tuple can be represented with (a,b). Ant they can be pattern matched and are one of the primitive type.

List

We have use List instead of Array.

[1..10]                                  --[1,2,3,4,5,6,7,8,9,10]
[(x,y)| x <- [1..10], y <- [1..10]]]     --[(1,1),(1,2)...
[a,b,c,d]
[a|[b,c,d]]
[x|xs]
[1|[2|[3|[4|[5,6,7]]]]]

Other syntax changes

While declaring class and instances we use Haskell's syntax.

 class Applicative m => Monad m

 instance Monad List where