Fridtjof Siebert

This small test ``` fold_test is n := (0..100000).fold i32.type.sum say n ``` results in a stack overflow ``` > $FUZION/bin/fz fold_test.fz 2>&1 | head -n 20 error 1: java.lang.StackOverflowError...

This adds a means to test and change a type constraint to fix #967. For this, it adds one feature ``` Type.infix : (T type) bool ``` This permits code...

Surprising difference between lambda and partial application

5

This results in `f` initialized with a lambda that calls `say` once, followed by a call to `say "ho"` that is executed when this is run ``` > ./build//bin/fz -e...

See this ``` > PRECONDITIONS=true POSTCONDITIONS=true ./build/bin/fz -e "x(v T) => _ := T" command line:1:1: error 1: Main feature must not have arguments x(v T) => _ := T...

See this: ``` > echo -n "blabla" | ./build/bin/fz - -:1:1: error 1: Could not find called feature blabl Feature not found: 'blabla' (no arguments) Target feature: 'universe' In call:...

`lib/io/buffered/reader.fz` currently uses a mutate effect to create a mutable variable ``` buffer := LM.env.new empty ``` that is later modified like this ``` buffer

`Mutable_Array` should expect type parameter `M type : mutate`

2

See idiom 196 for an example: Currently, it is possible to create a function that expects a `Mutable_Array` but not the `mutate` type this array was created for. This is...

In C backend, illegal access to mutable var is not detected

1

This example ``` m : mutate is s := m.go (() -> m.env.new 0) _ := s.get say "*** failed, should have panicked ***" ``` correctly panics using the JVM...

Usage of `:` in different contexts may be confusing

3

### Problem Fuzion uses `:` for a number of very different purposes: 1. to separate a feature signature from its inheritance calls `f32(public val f32) : float is` 2. to...

`Fixed feature is not implemented` error reports wrong call site

1

This example taken from #795 ``` test_fixed is a is fixed x => say "in a.x" b : a is a.x p ref a := b p.x # should cause...