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[FaberVitale]

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Math ops

For UX reasons, it would be better to not duplicate the math operators.

There are 2 possible better alternatives.

1. Overload operators (Rust, Elm)

• operator is overloaded and can be used for Int + Int and Float + Float.

Attempting to sum an Int with a Float is a compile time error.

    let a = 1.0 + 2; // error[E0277]: cannot add an integer to a float ❌

An explicit cast is required to sum integers

    let a = 1.0 + 2 as f32; // compiles ✅

2. Numeric promotion (Java approach)

In Java 1.0 + 2 Returns 3.0.
Numbers are automatically promoted, when necessary, in binary ops.

See 5.1.3 Narrowing Primitive Conversion

String concat operator

In SQL <> is the not equal operator.
It's confusing to use it for string concatenation.

Either +, ++ or :: are better alternatives.

[ascandone]

About the nums:
for the language to work without types it's crucial not to have polymorphic overloading. In other words, + has to have type Fn(Int, Int) -> Int and +. has to have type Fn(Float, Float) -> Float.
In order to be able to calculate 1 + 1.2 it's enough to expose a function int_to_float : Fn(Int) -> Float so that we don't need extra concepts in the language (e.g. as). This is actually already implemented in the kestrel_core library - currently private

About the strings:
Didn't think about it! <> is the str concat in elixir so I just went with this
But maybe ++ might be more natural 🤔

[ascandone]

Update 1: <> was changed into ++
Update 2: A simplified version of Haskell's type classes was introduced in #25. So far only the trait Show, Eq and Ord are included, but a Num type classes might be defined too, in order to solve the +, *, etc overloading problem.