use crate::{
binding::{encoding, string},
rubysys::string::{rstring_end, rstring_ptr},
types::{c_char, c_int, InternalValue},
EncodingSupport, Object, RString,
};
#[derive(Debug)]
pub struct CodepointIterator {
rstring: RString,
ptr: *const c_char,
}
impl CodepointIterator {
pub fn new(rstring: &RString) -> Self {
let fstring = string::new_frozen(rstring.value());
CodepointIterator {
rstring: RString::from(fstring),
ptr: unsafe { rstring_ptr(fstring) },
}
}
}
impl Iterator for CodepointIterator {
type Item = usize;
fn next(&mut self) -> Option<Self::Item> {
let mut n: c_int = 0;
let ptr = self.ptr;
let end = unsafe { rstring_end(self.rstring.value()) };
let enc = self.rstring.encoding();
if ptr < end {
let result = Some(encoding::next_codepoint(ptr, end, &mut n, enc.value()));
self.ptr = unsafe { ptr.add(n as usize) };
result
} else {
None
}
}
}