1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
//! Provides parsers for variables.
use nom::bytes::complete::tag;
use nom::combinator::map;
use nom::sequence::preceded;
use crate::parsers::{parse_name, ParseResult, Span};
use crate::types::Variable;
/// Parses a variable, i.e. `?<name>` and returns its name.
///
/// ## Example
/// ```
/// # use pddl::parsers::{parse_variable, preamble::*};
/// assert!(parse_variable(Span::new("?abcde")).is_value("abcde".into()));
/// assert!(parse_variable(Span::new("?a-1_2")).is_value("a-1_2".into()));
/// assert!(parse_variable(Span::new("?Z01")).is_value("Z01".into()));
/// assert!(parse_variable(Span::new("?x-_-_")).is_value("x-_-_".into()));
///
/// assert!(parse_variable(Span::new("abcde")).is_err());
/// assert!(parse_variable(Span::new("?-")).is_err());
/// assert!(parse_variable(Span::new("?1")).is_err());
///```
pub fn parse_variable<'a, T: Into<Span<'a>>>(input: T) -> ParseResult<'a, Variable> {
map(preceded(tag("?"), parse_name), Variable::from)(input.into())
}
impl crate::parsers::Parser for Variable {
type Item = Variable;
/// Parses a variable.
///
/// ## Example
/// ```
/// # use pddl::{Variable, Parser};
/// let (_, value) = Variable::parse("?abcde").unwrap();
/// assert_eq!(value, "abcde".into());
///```
///
/// ## See also
/// See [`parse_variable`].
fn parse<'a, S: Into<Span<'a>>>(input: S) -> ParseResult<'a, Self::Item> {
parse_variable(input)
}
}
#[cfg(test)]
mod tests {
use crate::{Parser, Variable};
#[test]
fn test_parse() {
let (_, value) = Variable::parse("?abcde").unwrap();
assert_eq!(value, "abcde".into());
}
}