`seq!`
======
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A `seq!` macro to repeat a fragment of source code and substitute into each
repetition a sequential numeric counter.
```toml
[dependencies]
seq-macro = "0.2"
```
```rust
#![feature(proc_macro_non_items)]
use seq_macro::seq;
fn main() {
let tuple = (1000, 100, 10);
let mut sum = 0;
// Expands to:
//
// sum += tuple.0;
// sum += tuple.1;
// sum += tuple.2;
//
// This cannot be written using an ordinary for-loop because elements of
// a tuple can only be accessed by their integer literal index, not by a
// variable.
seq!(N in 0..=2 {
sum += tuple.N;
});
assert_eq!(sum, 1110);
}
```
- If the input tokens contain a section surrounded by `#(` ... `)*` then only
that part is repeated.
- The numeric counter can be pasted onto the end of some prefix to form
sequential identifiers.
```rust
use seq_macro::seq;
seq!(N in 64..=127 {
#[derive(Debug)]
enum Demo {
// Expands to Variant64, Variant65, ...
#(
Variant#N,
)*
}
});
fn main() {
assert_eq!("Variant99", format!("{:?}", Demo::Variant99));
}
```
- Byte and character ranges are supported: `b'a'..=b'z'`, `'a'..='z'`.
- If the range bounds are written in binary, octal, hex, or with zero padding,
those features are preserved in any generated tokens.
```rust
use seq_macro::seq;
seq!(P in 0x000..=0x00F {
// expands to structs Pin000, ..., Pin009, Pin00A, ..., Pin00F
struct Pin#P;
});
```
<br>
#### License
<sup>
Licensed under either of <a href="LICENSE-APACHE">Apache License, Version
2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option.
</sup>
<br>
<sub>
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in this crate by you, as defined in the Apache-2.0 license, shall
be dual licensed as above, without any additional terms or conditions.
</sub>