Sze
January 19, 2024, 7:35am
5
Take a look at SubTuple here:
SubTuple does not work if low is greater than 0, because then the resulting type doesn’t have field names starting with 0 and thus isn’t a valid tuple, you need to reindex the fields similar to what extract does:
fn SubTuple(comptime T: type, comptime low: usize, comptime high: usize) type {
const info = @typeInfo(T);
const old_fields = std.meta.fields(T)[low..high];
var new_fields: [old_fields.len]std.builtin.Type.StructField = undefined;
for (old_fields, 0..) |old, i| {
…
The answer to this is that tuple fields need to start with names starting from 0, so you need to rebuild the type with the field names being reindexed, so that they start from 0.
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