Macro char_collect

macro_rules! char_collect {
    ({ $($x:tt)+ }) => { ... };
    ( $( $x:expr ),* ) => { ... };
}

Generate a [CharCollection] from a sequence of chars, CharRanges, or Unicode Blocks.

The macro can be used with either a comma-separated list of items, or with an expression representing set operations.

use char_collection::char_collect;
use unicode_blocks::UnicodeBlockId;
use unic_char_range::CharRange;

let c1 = char_collect!(
    'a'..='z',
    CharRange::closed('D', 'G'),
    UnicodeBlockId::Cyrillic,
    0x01..=0x05,
    '@');

let c2 = char_collect!({ ('a'..='z') - ('p'..='t') + UnicodeBlockId::Bengali });

NOTE: Parenthetical expressions currently aren’t supported unless they start with a CharCollection.

use char_collection::char_collect;

// This works:
let c1 = char_collect!({ ('a'..='z') + (char_collect!('A'..='Z') - ('L'..='P')) });

// This doesn't:
let c1 = char_collect!({ ('a'..='z') + (('A'..='Z') - ('L'..='P')) });