C error

[Eliyaan]

Describe the bug

The program produces a C error

Reproduction Steps

fn separate_wires(coo_adj_wires [][2]u32, id u64) {
        _ := [][2]u32{len: coo_adj_wires.len, init: coo_adj_wires[index]}
}

fn main() {
        separate_wires([[u32(1), 2]!], 0)
}

Expected Behavior

No C error.

Current Behavior

❯ v run rpdc.v
================== C compilation error (from tcc): ==============
cc: /tmp/v_1000/rpdc.01JKVAS7CTJXSHR3AWHCJSFHNR.tmp.c:5708: error: lvalue expected
=================================================================
(You can pass `-cg`, or `-show-c-output` as well, to print all the C error messages).
builder error:
==================
C error found. It should never happen, when compiling pure V code.

Possible Solution

No response

Additional Information/Context

No response

V version

V 0.4.9

Environment details (OS name and version, etc.)

V full version	V 0.4.9 6ac1d08.793487f
OS	linux, "Void Linux"
Processor	4 cpus, 64bit, little endian, Intel(R) Pentium(R) Gold 7505 @ 2.00GHz
Memory	5.97GB/23.16GB
V executable	/home/nopana/v/v
V last modified time	2025-02-11 18:44:27
V home dir	OK, value: /home/nopana/v
VMODULES	OK, value: /home/nopana/.vmodules
VTMP	OK, value: /tmp/v_1000
Current working dir	OK, value: /home/nopana/projects/notOnlyNots
Git version	git version 2.47.1
V git status	weekly.2025.04-76-g793487fd
.git/config present	true
cc version	cc (GCC) 13.2.0
gcc version	gcc (GCC) 13.2.0
clang version	N/A
tcc version	tcc version 0.9.28rc 2024-07-31 HEAD@1cee0908 (x86_64 Linux)
tcc git status	thirdparty-linux-amd64 0134e9b9
emcc version	N/A
glibc version	ldd (GNU libc) 2.39

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[huly-for-github]

Connected to Huly®: V_0.6-22113

[JalonSolov]

If you compile with -g, it tells you the error is on the last line of the example, the closing } for main.

[jorgeluismireles]

index is a typo in init: coo_adj_wires[index], so this works:

fn separate_wires(coo_adj_wires [][2]u32, id u64) {
        _ := [][2]u32{len: coo_adj_wires.len, init: coo_adj_wires[id]}
}

and when we type not index but other typo for instance inde a V error is thrown:

    1 | fn separate_wires(coo_adj_wires [][2]u32, id u64) {
    2 |         _ := [][2]u32{len: coo_adj_wires.len, init: coo_adj_wires[inde]}
      |                                                                   ~~~~
    3 | }
    4 |

[Eliyaan]

it is not a typo, index is a special variable that holds the index of the current element while creating the array.
example:

a := []int{len:3, init:index} // [0, 1, 2]