blob: ee86b809444e867e45ae915a0dbface77b1621da (
plain)
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
56
57
58
59
60
61
62
63
|
---
title: Conditionals
---
This page presents the computation operators that allow a choice depending on
some condition. All possible returned values must be of the same type.
### IF-ELSE
{{< fatecode >}}(if_else [BOOL] [C0 = COMPUTATION] [C1 = COMPUTATION]){{< /fatecode >}}
Returns `C0` is `[BOOL]` yields true, `C1` otherwise.
### COND
{{< fatecode >}}(cond
([B0 = BOOL] [C0 = COMPUTATION])
...
([BN = BOOL] [CN = COMPUTATION])
){{< /fatecode >}}
Returns `[CI]`, such that `[BI]` is the first to hold true. If there is not such
`Bi`, returns `[CN]`.
### SWITCH
{{< fatecode >}}(switch [T = COMPUTATION]
([V0 = COMPUTATION] [C0 = COMPUTATION])
...
([VN = BOOL] [CN = COMPUTATION])
[D = COMPUTATION]
){{< /fatecode >}}a
Returns the first `CI` such that `VI` is equal to `T`. If there is not such
`VI`, returns `[D]`.
## Examples
{{< fatecode >}}(cond
((false) (false))
((false) (false))
((true)
(cond
((false) (false))
((true) (not (is_member 3 test_list)))
((true) (false))
)
)
)
{{< /fatecode >}}
{{< fatecode >}}(switch 3
(0 (false))
(1 (false))
(3 (true))
(2 (false))
(false)
)
{{< /fatecode >}}
{{< fatecode >}}(if_else (true)
(if_else (false)
(assert (false) FAILED: instruction ifelse E)
(set test_var (true))
)
(assert (false) FAILED: instruction ifelse F)
)
{{< /fatecode >}}
|
