mv inline span structs to span module

This commit is contained in:
Noah Hellman 2023-01-15 16:12:05 +01:00
parent 59664feaf3
commit 0816ab4dcb
2 changed files with 203 additions and 193 deletions

View file

@ -7,6 +7,7 @@ mod lex;
mod span;
mod tree;
use span::DiscontinuousString;
use span::Span;
pub use attr::Attributes;
@ -254,201 +255,11 @@ impl<'s> Container<'s> {
}
}
#[derive(Clone)]
struct InlineChars<'s, I> {
src: &'s str,
inlines: I,
next: std::str::Chars<'s>,
}
// Implement inlines.flat_map(|sp| sp.of(self.src).chars())
impl<'s, I: Iterator<Item = Span>> InlineChars<'s, I> {
fn new(src: &'s str, inlines: I) -> Self {
Self {
src,
inlines,
next: "".chars(),
}
}
}
impl<'s, I: Iterator<Item = Span>> Iterator for InlineChars<'s, I> {
type Item = char;
fn next(&mut self) -> Option<Self::Item> {
(&mut self.inlines)
.flat_map(|sp| sp.of(self.src).chars())
.next()
}
}
trait DiscontinuousString<'s> {
type Chars: Iterator<Item = char>;
fn src(&self, span: Span) -> CowStr<'s>;
fn chars(&self) -> Self::Chars;
}
impl<'s> DiscontinuousString<'s> for &'s str {
type Chars = std::str::Chars<'s>;
fn src(&self, span: Span) -> CowStr<'s> {
span.of(self).into()
}
fn chars(&self) -> Self::Chars {
str::chars(self)
}
}
impl<'s> DiscontinuousString<'s> for InlineSpans<'s> {
type Chars = InlineCharsIter<'s>;
fn src(&self, span: Span) -> CowStr<'s> {
Self::borrow_or_copy(self.src, self.spans.iter().copied(), span)
}
fn chars(&self) -> Self::Chars {
// SAFETY: do not call set_spans while chars is in use
unsafe { std::mem::transmute(InlineChars::new(self.src, self.spans.iter().copied())) }
}
}
impl<'s, 'i> DiscontinuousString<'s> for InlineSpansSlice<'s, 'i> {
type Chars = InlineChars<'s, InlineSpansSliceIter<'i>>;
/// Borrow if continuous, copy if discontiunous.
fn src(&self, span: Span) -> CowStr<'s> {
InlineSpans::borrow_or_copy(self.src, self.spans(), span)
}
fn chars(&self) -> Self::Chars {
InlineChars::new(self.src, self.spans())
}
}
#[derive(Default, Debug)]
struct InlineSpans<'s> {
src: &'s str,
spans: Vec<Span>,
}
impl<'s> InlineSpans<'s> {
fn new(src: &'s str) -> Self {
Self {
src,
spans: Vec::new(),
}
}
fn set_spans(&mut self, spans: impl Iterator<Item = Span>) {
self.spans.clear();
self.spans.extend(spans);
}
fn slice<'i>(&'i self, span: Span) -> InlineSpansSlice<'s, 'i> {
let mut first = 0;
let mut last = 0;
let mut first_skip = 0;
let mut last_len = 0;
let mut a = 0;
for (i, sp) in self.spans.iter().enumerate() {
let b = a + sp.len();
if span.start() < b {
if a <= span.start() {
first = i;
first_skip = span.start() - a;
if span.end() <= b {
// continuous
last = i;
last_len = span.len();
break;
}
} else {
last = i;
last_len = sp.len().min(span.end() - a);
break;
};
}
a = b;
}
assert_ne!(last_len, 0);
InlineSpansSlice {
src: self.src,
first_skip,
last_len,
spans: &self.spans[first..=last],
}
}
/// Borrow if continuous, copy if discontiunous.
fn borrow_or_copy<I: Iterator<Item = Span>>(src: &str, spans: I, span: Span) -> CowStr {
let mut a = 0;
let mut s = String::new();
for sp in spans {
let b = a + sp.len();
if span.start() < b {
let r = if a <= span.start() {
if span.end() <= b {
// continuous
return CowStr::Borrowed(&sp.of(src)[span.start() - a..span.end() - a]);
}
(span.start() - a)..sp.len()
} else {
0..sp.len().min(span.end() - a)
};
s.push_str(&sp.of(src)[r]);
}
a = b;
}
assert_eq!(span.len(), s.len());
CowStr::Owned(s)
}
}
struct InlineSpansSlice<'s, 'i> {
src: &'s str,
first_skip: usize,
last_len: usize,
spans: &'i [Span],
}
type InlineSpansSliceIter<'i> = std::iter::Chain<
std::iter::Chain<std::iter::Once<Span>, std::iter::Copied<std::slice::Iter<'i, Span>>>,
std::iter::Once<Span>,
>;
impl<'s, 'i> InlineSpansSlice<'s, 'i> {
fn spans(&self) -> InlineSpansSliceIter<'i> {
let (span_start, r_middle, span_end) = if self.spans.len() == 1 {
(
Span::by_len(self.spans[0].start() + self.first_skip, self.last_len),
0..0,
Span::by_len(self.spans[self.spans.len() - 1].start(), 0),
)
} else {
(
Span::new(self.spans[0].start() + self.first_skip, self.spans[0].end()),
1..self.spans.len().saturating_sub(2),
Span::by_len(self.spans[self.spans.len() - 1].start(), self.last_len),
)
};
std::iter::once(span_start)
.chain(self.spans[r_middle].iter().copied())
.chain(std::iter::once(span_end))
}
}
type InlineCharsIter<'s> = InlineChars<'s, std::iter::Copied<std::slice::Iter<'static, Span>>>;
pub struct Parser<'s> {
src: &'s str,
tree: block::Tree,
inlines: InlineSpans<'s>,
inline_parser: Option<inline::Parser<InlineCharsIter<'s>>>,
inlines: span::InlineSpans<'s>,
inline_parser: Option<inline::Parser<span::InlineCharsIter<'s>>>,
inline_start: usize,
}
@ -458,7 +269,7 @@ impl<'s> Parser<'s> {
Self {
src,
tree: block::parse(src),
inlines: InlineSpans::new(src),
inlines: span::InlineSpans::new(src),
inline_parser: None,
inline_start: 0,
}

View file

@ -1,3 +1,5 @@
use crate::CowStr;
#[derive(Clone, Copy, Default, Debug, PartialEq, Eq)]
pub struct Span {
start: u32,
@ -84,6 +86,203 @@ impl Span {
}
}
pub trait DiscontinuousString<'s> {
type Chars: Iterator<Item = char>;
fn src(&self, span: Span) -> CowStr<'s>;
fn chars(&self) -> Self::Chars;
}
impl<'s> DiscontinuousString<'s> for &'s str {
type Chars = std::str::Chars<'s>;
fn src(&self, span: Span) -> CowStr<'s> {
span.of(self).into()
}
fn chars(&self) -> Self::Chars {
str::chars(self)
}
}
/// Multiple discontinuous [`std::str::Chars`] objects concatenated.
#[derive(Clone)]
pub struct InlineChars<'s, I> {
src: &'s str,
inlines: I,
next: std::str::Chars<'s>,
}
// Implement inlines.flat_map(|sp| sp.of(self.src).chars())
impl<'s, I: Iterator<Item = Span>> InlineChars<'s, I> {
fn new(src: &'s str, inlines: I) -> Self {
Self {
src,
inlines,
next: "".chars(),
}
}
}
impl<'s, I: Iterator<Item = Span>> Iterator for InlineChars<'s, I> {
type Item = char;
fn next(&mut self) -> Option<Self::Item> {
if self.next.as_str().is_empty() {
self.next = self
.inlines
.next()
.map_or_else(|| "".chars(), |sp| sp.of(self.src).chars());
}
self.next.next()
}
}
pub type InlineCharsIter<'s> = InlineChars<'s, std::iter::Copied<std::slice::Iter<'static, Span>>>;
#[derive(Default, Debug)]
pub struct InlineSpans<'s> {
src: &'s str,
spans: Vec<Span>,
}
impl<'s> InlineSpans<'s> {
pub fn new(src: &'s str) -> Self {
Self {
src,
spans: Vec::new(),
}
}
pub fn set_spans(&mut self, spans: impl Iterator<Item = Span>) {
self.spans.clear();
self.spans.extend(spans);
}
pub fn slice<'i>(&'i self, span: Span) -> InlineSpansSlice<'s, 'i> {
let mut first = 0;
let mut last = 0;
let mut first_skip = 0;
let mut last_len = 0;
let mut a = 0;
for (i, sp) in self.spans.iter().enumerate() {
let b = a + sp.len();
if span.start() < b {
if a <= span.start() {
first = i;
first_skip = span.start() - a;
if span.end() <= b {
// continuous
last = i;
last_len = span.len();
break;
}
} else {
last = i;
last_len = sp.len().min(span.end() - a);
break;
};
}
a = b;
}
assert_ne!(last_len, 0);
InlineSpansSlice {
src: self.src,
first_skip,
last_len,
spans: &self.spans[first..=last],
}
}
/// Borrow if continuous, copy if discontiunous.
fn borrow_or_copy<I: Iterator<Item = Span>>(src: &str, spans: I, span: Span) -> CowStr {
let mut a = 0;
let mut s = String::new();
for sp in spans {
let b = a + sp.len();
if span.start() < b {
let r = if a <= span.start() {
if span.end() <= b {
// continuous
return CowStr::Borrowed(&sp.of(src)[span.start() - a..span.end() - a]);
}
(span.start() - a)..sp.len()
} else {
0..sp.len().min(span.end() - a)
};
s.push_str(&sp.of(src)[r]);
}
a = b;
}
assert_eq!(span.len(), s.len());
CowStr::Owned(s)
}
}
impl<'s> DiscontinuousString<'s> for InlineSpans<'s> {
type Chars = InlineCharsIter<'s>;
fn src(&self, span: Span) -> CowStr<'s> {
Self::borrow_or_copy(self.src, self.spans.iter().copied(), span)
}
fn chars(&self) -> Self::Chars {
// SAFETY: do not call set_spans while chars is in use
unsafe { std::mem::transmute(InlineChars::new(self.src, self.spans.iter().copied())) }
}
}
/// A read-only slice of an [`InlineSpans`] object.
pub struct InlineSpansSlice<'s, 'i> {
src: &'s str,
first_skip: usize,
last_len: usize,
spans: &'i [Span],
}
impl<'s, 'i> InlineSpansSlice<'s, 'i> {
fn spans(&self) -> InlineSpansSliceIter<'i> {
let (span_start, r_middle, span_end) = if self.spans.len() == 1 {
(
Span::by_len(self.spans[0].start() + self.first_skip, self.last_len),
0..0,
Span::by_len(self.spans[self.spans.len() - 1].start(), 0),
)
} else {
(
Span::new(self.spans[0].start() + self.first_skip, self.spans[0].end()),
1..self.spans.len().saturating_sub(2),
Span::by_len(self.spans[self.spans.len() - 1].start(), self.last_len),
)
};
std::iter::once(span_start)
.chain(self.spans[r_middle].iter().copied())
.chain(std::iter::once(span_end))
}
}
impl<'s, 'i> DiscontinuousString<'s> for InlineSpansSlice<'s, 'i> {
type Chars = InlineChars<'s, InlineSpansSliceIter<'i>>;
/// Borrow if continuous, copy if discontiunous.
fn src(&self, span: Span) -> CowStr<'s> {
InlineSpans::borrow_or_copy(self.src, self.spans(), span)
}
fn chars(&self) -> Self::Chars {
InlineChars::new(self.src, self.spans())
}
}
type InlineSpansSliceIter<'i> = std::iter::Chain<
std::iter::Chain<std::iter::Once<Span>, std::iter::Copied<std::slice::Iter<'i, Span>>>,
std::iter::Once<Span>,
>;
#[cfg(test)]
mod test {
use super::Span;