aboutsummaryrefslogtreecommitdiff
path: root/README.md
blob: 7407bb2f5a28b80c3164f5251f27c58959195ad2 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
# clean-compiler

The [Clean][clean] compiler.

The official Clean compiler can be found at
[https://svn.cs.ru.nl/repos/clean-compiler/][cocl].
This is a fork to implement experimental new features.

---

## Contents

1\. [Syntactic sugar](#1-syntactic-sugar)  
1.1. [Lambda-case](#11-lambda-case)

---

## 1. Syntactic sugar

### 1.1. Lambda-case

Similar to [GHC's LambdaCase][ghclambdacase], this is a sugar for lambda
expressions where the argument is only used in a `case .. of` expression. For
example,

```clean
\case of
	0 = "zero"
	1 = "one"
	_ = "many"
```

is transformed to

```clean
\x -> case x of
	0 = "zero"
	1 = "one"
	_ = "many"
```

where `x` is a fresh variable.

The `of` is optional (though recommended to distinguish Clean from Haskell).

The extension to the grammar:

```
LambdaAbstr = ...
            | \case [of] {CaseAltDef}+
```

[clean]: http://clean.cs.ru.nl
[cocl]: https://svn.cs.ru.nl/repos/clean-compiler/
[ghclambdacase]: https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/glasgow_exts.html#lambda-case