Removes some allocations

Signed-off-by: Hanif Bin Ariffin <hanif.ariffin.4326@gmail.com>
This commit is contained in:
Hanif Bin Ariffin 2021-07-20 17:04:05 +08:00
parent c3bd727f8d
commit 0254ceb48b

View file

@ -1,8 +1,9 @@
use crate::unicode_table;
use nom::{
branch::alt,
bytes::complete::{tag, take_while1},
character::complete::{anychar, one_of},
combinator::{map_opt, recognize, value},
combinator::{map_opt, recognize},
multi::{many0, many_m_n},
sequence::{preceded, separated_pair, tuple},
IResult,
@ -13,12 +14,20 @@ use std::{
io::{BufRead, Write},
};
use crate::unicode_table;
static SPACES: &'static [char] = &[
unicode_table::HT,
unicode_table::LF,
unicode_table::VT,
unicode_table::FF,
unicode_table::CR,
unicode_table::SPACE,
];
static BLANK: &'static [char] = &[unicode_table::SPACE, unicode_table::HT];
#[derive(Debug, PartialEq, Eq, Clone)]
pub enum Sequence {
Char(char),
CharRange(Vec<char>),
CharRange(Box<dyn Iterator<Item = char>>),
CharStar(char),
}
impl Sequence {
@ -53,10 +62,11 @@ impl Sequence {
.unwrap()
}
pub fn dissolve(self) -> Vec<char> {
pub fn dissolve(self) -> Box<dyn Iterator<Item = char>> {
match self {
Sequence::Char(c) => vec![c],
Sequence::Char(c) => Box::new(std::iter::once(c)),
Sequence::CharRange(r) => r,
Sequence::CharStar(c) => Box::new(std::iter::repeat(c)),
}
}
@ -97,13 +107,14 @@ impl Sequence {
separated_pair(anychar, tag("-"), anychar)(input).map(|(l, (a, b))| {
(l, {
let (start, end) = (u32::from(a), u32::from(b));
Sequence::CharRange((start..=end).filter_map(std::char::from_u32).collect())
Sequence::CharRange(Box::new((start..=end).filter_map(std::char::from_u32)))
})
})
}
fn parse_char_star(input: &str) -> IResult<&str, Sequence> {
tuple((tag("["), anychar, tag("*]")))(input).map(|(_, (_, _, _))| todo!())
tuple((tag("["), anychar, tag("*]")))(input)
.map(|(l, (_, c, _))| (l, Sequence::CharStar(c)))
}
fn parse_char_repeat(input: &str) -> IResult<&str, Sequence> {
@ -118,7 +129,7 @@ impl Sequence {
.map(|(l, (_, c, _, n, _))| {
(
l,
Sequence::CharRange(std::iter::repeat(c).take(n.parse().unwrap()).collect()),
Sequence::CharRange(Box::new(std::iter::repeat(c).take(n.parse().unwrap()))),
)
})
}
@ -127,104 +138,118 @@ impl Sequence {
tag("[:alnum:]")(input).map(|(l, _)| {
(
l,
Sequence::CharRange(('0'..='9').chain('A'..='Z').chain('a'..='z').collect()),
Sequence::CharRange(Box::new(('0'..='9').chain('A'..='Z').chain('a'..='z'))),
)
})
}
fn parse_alpha(input: &str) -> IResult<&str, Sequence> {
value(
Sequence::CharRange(('A'..='Z').chain('a'..='z').collect()),
tag("[:alpha:]"),
)(input)
tag("[:alpha:]")(input).map(|(l, _)| {
(
l,
Sequence::CharRange(Box::new(('A'..='Z').chain('a'..='z'))),
)
})
}
fn parse_blank(input: &str) -> IResult<&str, Sequence> {
value(
Sequence::CharRange(vec![unicode_table::SPACE, unicode_table::HT]),
tag("[:blank:]"),
)(input)
tag("[:blank:]")(input)
.map(|(l, _)| (l, Sequence::CharRange(Box::new(BLANK.into_iter().cloned()))))
}
fn parse_control(input: &str) -> IResult<&str, Sequence> {
value(
Sequence::CharRange(
(0..=31)
.chain(std::iter::once(127))
.flat_map(char::from_u32)
.collect(),
),
tag("[:cntrl:]"),
)(input)
tag("[:cntrl:]")(input).map(|(l, _)| {
(
l,
Sequence::CharRange(Box::new(
(0..=31)
.chain(std::iter::once(127))
.flat_map(char::from_u32),
)),
)
})
}
fn parse_digit(input: &str) -> IResult<&str, Sequence> {
value(Sequence::CharRange(('0'..='9').collect()), tag("[:digit:]"))(input)
tag("[:digit:]")(input).map(|(l, _)| (l, Sequence::CharRange(Box::new('0'..='9'))))
}
fn parse_graph(input: &str) -> IResult<&str, Sequence> {
value(
Sequence::CharRange(
(48..=57) // digit
.chain(65..=90) // uppercase
.chain(97..=122) // lowercase
// punctuations
.chain(33..=47)
.chain(58..=64)
.chain(91..=96)
.chain(123..=126)
.flat_map(char::from_u32)
.collect(),
),
tag("[:graph:]"),
)(input)
tag("[:graph:]")(input).map(|(l, _)| {
(
l,
Sequence::CharRange(Box::new(
(48..=57) // digit
.chain(65..=90) // uppercase
.chain(97..=122) // lowercase
// punctuations
.chain(33..=47)
.chain(58..=64)
.chain(91..=96)
.chain(123..=126)
.chain(std::iter::once(32)) // space
.flat_map(char::from_u32),
)),
)
})
}
fn parse_lower(input: &str) -> IResult<&str, Sequence> {
value(Sequence::CharRange(('a'..='z').collect()), tag("[:lower:]"))(input)
tag("[:lower:]")(input).map(|(l, _)| (l, Sequence::CharRange(Box::new('a'..='z'))))
}
fn parse_print(input: &str) -> IResult<&str, Sequence> {
tag("[:print:]")(input).map(|(_, _)| todo!())
tag("[:print:]")(input).map(|(l, _)| {
(
l,
Sequence::CharRange(Box::new(
(48..=57) // digit
.chain(65..=90) // uppercase
.chain(97..=122) // lowercase
// punctuations
.chain(33..=47)
.chain(58..=64)
.chain(91..=96)
.chain(123..=126)
.flat_map(char::from_u32),
)),
)
})
}
fn parse_punct(input: &str) -> IResult<&str, Sequence> {
value(
Sequence::CharRange(
(33..=47)
.chain(58..=64)
.chain(91..=96)
.chain(123..=126)
.flat_map(char::from_u32)
.collect(),
),
tag("[:punct:]"),
)(input)
tag("[:punct:]")(input).map(|(l, _)| {
(
l,
Sequence::CharRange(Box::new(
(33..=47)
.chain(58..=64)
.chain(91..=96)
.chain(123..=126)
.flat_map(char::from_u32),
)),
)
})
}
fn parse_space(input: &str) -> IResult<&str, Sequence> {
value(
Sequence::CharRange(vec![
unicode_table::HT,
unicode_table::LF,
unicode_table::VT,
unicode_table::FF,
unicode_table::CR,
unicode_table::SPACE,
]),
tag("[:space:]"),
)(input)
tag("[:space:]")(input).map(|(l, _)| {
(
l,
Sequence::CharRange(Box::new(SPACES.into_iter().cloned())),
)
})
}
fn parse_upper(input: &str) -> IResult<&str, Sequence> {
tag("[:upper:]")(input).map(|(l, _)| (l, Sequence::CharRange(('A'..='Z').collect())))
tag("[:upper:]")(input).map(|(l, _)| (l, Sequence::CharRange(Box::new('A'..='Z'))))
}
fn parse_xdigit(input: &str) -> IResult<&str, Sequence> {
tag("[:xdigit:]")(input).map(|(l, _)| {
(
l,
Sequence::CharRange(('0'..='9').chain('A'..='F').chain('a'..='f').collect()),
Sequence::CharRange(Box::new(('0'..='9').chain('A'..='F').chain('a'..='f'))),
)
})
}
@ -238,16 +263,18 @@ pub trait SymbolTranslator {
fn translate(&mut self, current: char) -> Option<char>;
}
#[derive(Debug, Clone)]
pub struct DeleteOperation {
set: Vec<Sequence>,
set: Vec<char>,
complement_flag: bool,
}
impl DeleteOperation {
pub fn new(set: Vec<Sequence>, complement_flag: bool) -> DeleteOperation {
DeleteOperation {
set,
set: set
.into_iter()
.flat_map(Sequence::dissolve)
.collect::<Vec<_>>(),
complement_flag,
}
}
@ -255,10 +282,7 @@ impl DeleteOperation {
impl SymbolTranslator for DeleteOperation {
fn translate(&mut self, current: char) -> Option<char> {
let found = self.set.iter().any(|sequence| match sequence {
Sequence::Char(c) => c.eq(&current),
Sequence::CharRange(r) => r.iter().any(|c| c.eq(&current)),
});
let found = self.set.iter().any(|sequence| sequence.eq(&current));
(self.complement_flag == found).then(|| current)
}
}
@ -463,41 +487,6 @@ where
}
}
#[test]
fn test_parse_char_range() {
assert_eq!(Sequence::parse_set_string(""), vec![]);
assert_eq!(
Sequence::parse_set_string("a-z"),
vec![Sequence::CharRange(vec![
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q',
'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
])]
);
assert_eq!(
Sequence::parse_set_string("a-zA-Z"),
vec![
Sequence::CharRange(vec![
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p',
'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
]),
Sequence::CharRange(vec![
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
])
]
);
assert_eq!(
Sequence::parse_set_string(", ┬─┬"),
vec![
Sequence::Char(','),
Sequence::Char(' '),
Sequence::Char('┬'),
Sequence::Char('─'),
Sequence::Char('┬')
]
);
}
#[test]
fn test_parse_octal() {
for a in '0'..='7' {