Cannot use closures as a final statement in an if/else block

[zeozeozeo]

V doctor:

V full version: V 0.4.3 5306469.10d738c
OS: windows, Microsoft Windows 10 Pro v19045 64-bit
Processor: 20 cpus, 64bit, little endian, 

getwd: C:\Users\user\Desktop\Code\leaflang
vexe: C:\Users\user\Desktop\Code\v\v.exe
vexe mtime: 2024-01-06 12:34:25

vroot: OK, value: C:\Users\user\Desktop\Code\v
VMODULES: OK, value: C:\Users\user\.vmodules
VTMP: OK, value: C:\Users\user\AppData\Local\Temp\v_0

Git version: git version 2.42.0.windows.1
Git vroot status: weekly.2024.01.test2-7-g10d738c7
.git/config present: true

CC version: Error: 'cc' is not recognized as an internal or external command,

operable program or batch file.


thirdparty/tcc status: thirdparty-windows-amd64 a39eb79b

What did you do?
v -g -o vdbg cmd/v && vdbg test.v

fn main() {
	x := 5
	f := if x == 5 { |x| x - 5 } else { |x| x }
	println(f(x))
}

What did you expect to see?

0 in stdout

What did you see instead?

test.v:3:19: error: a lambda expression was used, but `void` was expected
    1 | fn main() {
    2 |     x := 5
    3 |     f := if x == 5 { |x| x - 5 } else { |x| x }
      |                      ^
    4 |     println(f(x))
    5 | }
test.v:3:19: error: a lambda expression was used, but `none` was expected
    1 | fn main() {
    2 |     x := 5
    3 |     f := if x == 5 { |x| x - 5 } else { |x| x }
      |                      ^
    4 |     println(f(x))
    5 | }
test.v:3:19: error: the final expression in `if` or `match`, must have a value of a non-void type
    1 | fn main() {
    2 |     x := 5
    3 |     f := if x == 5 { |x| x - 5 } else { |x| x }
      |                      ^
    4 |     println(f(x))
    5 | }
test.v:3:4: error: assignment mismatch: 1 variable(s) 0 value(s)
    1 | fn main() {
    2 |     x := 5
    3 |     f := if x == 5 { |x| x - 5 } else { |x| x }
      |       ~~
    4 |     println(f(x))
    5 | }
test.v:3:19: error: a lambda expression was used, but `string` was expected
    1 | fn main() {
    2 |     x := 5
    3 |     f := if x == 5 { |x| x - 5 } else { |x| x }
      |                      ^
    4 |     println(f(x))
    5 | }
test.v:4:10: error: unknown function: f
    2 |     x := 5
    3 |     f := if x == 5 { |x| x - 5 } else { |x| x }
    4 |     println(f(x))
      |             ~~~~
    5 | }
test.v:4:2: error: `println` can not print void expressions
    2 |     x := 5
    3 |     f := if x == 5 { |x| x - 5 } else { |x| x }
    4 |     println(f(x))
      |     ~~~~~~~~~~~~~
    5 | }
If the code of your project is in multiple files, try with `v .` instead of `v test.v`

Example of this expression in Rust: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=60a8125c5277fb69cf22f9272f60aba7

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[shove70]

Please refer to:
#19874