#![cfg(feature = "parsing")]
use nom::{IResult, multispace};
use unicode_xid::UnicodeXID;
macro_rules! punct {
($i:expr, $punct:expr) => {
$crate::helper::punct($i, $punct)
};
}
pub fn punct<'a>(input: &'a str, token: &'static str) -> IResult<&'a str, &'a str> {
for (i, ch) in input.char_indices() {
if !ch.is_whitespace() {
return if input[i..].starts_with(token) {
IResult::Done(&input[i + token.len()..], token)
} else {
IResult::Error
};
}
}
IResult::Error
}
macro_rules! keyword {
($i:expr, $keyword:expr) => {
$crate::helper::keyword($i, $keyword)
};
}
pub fn keyword<'a>(input: &'a str, token: &'static str) -> IResult<&'a str, &'a str> {
match punct(input, token) {
IResult::Done(rest, _) => {
match word_break(rest) {
IResult::Done(_, _) => IResult::Done(rest, token),
IResult::Error => IResult::Error,
}
}
IResult::Error => IResult::Error,
}
}
pub fn word_break<'a>(input: &'a str) -> IResult<&'a str, ()> {
match input.chars().next() {
Some(ch) if UnicodeXID::is_xid_continue(ch) => {
IResult::Error
}
Some(_) | None => {
IResult::Done(input, ())
}
}
}
macro_rules! option {
($i:expr, $submac:ident!( $($args:tt)* )) => {
match $submac!($i, $($args)*) {
$crate::nom::IResult::Done(i, o) => $crate::nom::IResult::Done(i, Some(o)),
$crate::nom::IResult::Error => $crate::nom::IResult::Done($i, None),
}
};
($i:expr, $f:expr) => {
option!($i, call!($f));
};
}
macro_rules! opt_vec {
($i:expr, $submac:ident!( $($args:tt)* )) => {
match $submac!($i, $($args)*) {
$crate::nom::IResult::Done(i, o) => $crate::nom::IResult::Done(i, o),
$crate::nom::IResult::Error => $crate::nom::IResult::Done($i, Vec::new()),
}
};
}
macro_rules! epsilon {
($i:expr,) => {
$crate::nom::IResult::Done($i, ())
};
}
macro_rules! tap {
($i:expr, $name:ident : $submac:ident!( $($args:tt)* ) => $e:expr) => {
match $submac!($i, $($args)*) {
$crate::nom::IResult::Done(i, o) => {
let $name = o;
$e;
$crate::nom::IResult::Done(i, ())
}
$crate::nom::IResult::Error => $crate::nom::IResult::Error,
}
};
($i:expr, $name:ident : $f:expr => $e:expr) => {
tap!($i, $name: call!($f) => $e);
};
}
pub fn eat_spaces(input: &str) -> &str {
match multispace(input) {
IResult::Done(rest, _) => rest,
IResult::Error => input,
}
}