use crate::{ParseResult, Parser, ParserExt, ParserHandle, ParserOutput, ParserRegistry};
use regex::{Captures, Regex};
pub mod shorthand {
use super::*;
pub fn template(
parser: ParserHandle,
rule: Option<String>,
content: impl ToString,
) -> ParserHandle {
TemplateParser::new(parser, rule, content).into_handle()
}
}
thread_local! {
static REGEX: Regex = Regex::new(r"@(>|<)\{([^\}]*)\}\[([^\]@]*)\]\{([^\}]*)\}(\[(\d+)\])?@").unwrap();
}
pub struct TemplateParser {
parser: ParserHandle,
rule: Option<String>,
content: String,
}
impl TemplateParser {
pub fn new(parser: ParserHandle, rule: Option<String>, content: impl ToString) -> Self {
Self {
parser,
rule,
content: content.to_string(),
}
}
}
impl Parser for TemplateParser {
fn parse<'a>(&self, registry: &ParserRegistry, input: &'a str) -> ParseResult<'a> {
let (input, result) = self.parser.parse(registry, input)?;
let content =
if let Some(value) = result.read::<String>() {
self.content.replace("@{}@", &value)
} else if let Some(list) = result.read::<Vec<ParserOutput>>() {
REGEX.with(|regex| {
regex
.replace_all(&self.content, |caps: &Captures| -> String {
let ordering = caps.get(1).unwrap().as_str();
let prefix = caps.get(2).unwrap().as_str();
let delimiter = caps.get(3).unwrap().as_str();
let suffix = caps.get(4).unwrap().as_str();
let mut result = String::default();
if let Some(index) = caps.get(6) {
let index = index.as_str().parse::<usize>().unwrap();
result.push_str(prefix);
let item = list
.get(index)
.unwrap_or_else(|| {
panic!("Template parsing result list has no item at {index} index!")
})
.read::<String>()
.unwrap_or_else(|| {
panic!("Template parsing result list item {index} is not String!")
});
result.push_str(item.as_str());
result.push_str(suffix);
} else if ordering == ">" {
for (index, item) in list.iter().enumerate() {
if index > 0 {
result.push_str(delimiter);
}
result.push_str(prefix);
let item = item.read::<String>().unwrap_or_else(|| {
panic!("Template parsing result list item {index} is not String!")
});
result.push_str(item.as_str());
result.push_str(suffix);
}
} else if ordering == "<" {
for (index, item) in list.iter().rev().enumerate() {
if index > 0 {
result.push_str(delimiter);
}
result.push_str(prefix);
let item = item.read::<String>().unwrap_or_else(|| {
panic!("Template parsing result list item {index} is not String!")
});
result.push_str(item.as_str());
result.push_str(suffix);
}
}
result
})
.to_string()
})
} else {
return Err("Template parsing result is not String or Vec<ParserOutput>!".into());
};
if let Some(rule) = self.rule.as_ref() {
let (rest, result) = registry.parse(rule, &content)?;
if rest.is_empty() {
Ok((input, result))
} else {
Err("Templating content parsing did not consumed all source!".into())
}
} else {
Ok((input, ParserOutput::new(content).ok().unwrap()))
}
}
fn extend(&self, parser: ParserHandle) {
self.parser.extend(parser);
}
}
#[cfg(test)]
mod tests {
use crate::{
ParserOutput, ParserRegistry,
shorthand::{inject, lit, map, number_int, prefix, seq_del, source, template, ws},
template::TemplateParser,
};
fn is_async<T: Send + Sync>() {}
#[test]
fn test_template() {
is_async::<TemplateParser>();
let registry = ParserRegistry::default()
.with_parser(
"value",
map(prefix(number_int(), lit("value:")), |value: String| {
value.parse::<i32>().unwrap()
}),
)
.with_parser(
"add",
map(
seq_del(lit("+"), [inject("value"), inject("value")]),
|mut values: Vec<ParserOutput>| {
let b = values.remove(1).consume::<i32>().ok().unwrap();
let a = values.remove(0).consume::<i32>().ok().unwrap();
a + b
},
),
)
.with_parser(
"sub",
map(
seq_del(lit("-"), [inject("value"), inject("value")]),
|mut values: Vec<ParserOutput>| {
let b = values.remove(1).consume::<i32>().ok().unwrap();
let a = values.remove(0).consume::<i32>().ok().unwrap();
a - b
},
),
)
.with_parser(
"mul",
map(
seq_del(lit("*"), [inject("value"), inject("value")]),
|mut values: Vec<ParserOutput>| {
let b = values.remove(1).consume::<i32>().ok().unwrap();
let a = values.remove(0).consume::<i32>().ok().unwrap();
a * b
},
),
)
.with_parser(
"template_value",
template(source(number_int()), Some("value".to_owned()), "value:@{}@"),
)
.with_parser(
"template_add",
template(
seq_del(
ws(),
[
source(inject("template_value")),
source(inject("template_value")),
],
),
Some("add".to_owned()),
"@>{value:}[+]{}@",
),
)
.with_parser(
"template_sub",
template(
seq_del(
ws(),
[
source(inject("template_value")),
source(inject("template_value")),
],
),
Some("sub".to_owned()),
"@<{value:}[-]{}@",
),
)
.with_parser(
"template_mul",
template(
seq_del(
ws(),
[
source(inject("template_value")),
source(inject("template_value")),
],
),
Some("mul".to_owned()),
"value:@>{}[]{}[0]@*value:@>{}[]{}[1]@",
),
)
.with_parser(
"template_output",
template(source(inject("template_value")), None, "#@{}@"),
);
let (rest, result) = registry.parse("value", "value:42").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<i32>().ok().unwrap(), 42);
let (rest, result) = registry.parse("add", "value:40+value:2").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<i32>().ok().unwrap(), 42);
let (rest, result) = registry.parse("sub", "value:40-value:2").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<i32>().ok().unwrap(), 38);
let (rest, result) = registry.parse("mul", "value:6*value:4").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<i32>().ok().unwrap(), 24);
let (rest, result) = registry.parse("template_value", "42").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<i32>().ok().unwrap(), 42);
let (rest, result) = registry.parse("template_add", "40 2").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<i32>().ok().unwrap(), 42);
let (rest, result) = registry.parse("template_sub", "2 40").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<i32>().ok().unwrap(), 38);
let (rest, result) = registry.parse("template_mul", "6 4").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<i32>().ok().unwrap(), 24);
let (rest, result) = registry.parse("template_output", "42").unwrap();
assert_eq!(rest, "");
assert_eq!(result.consume::<String>().ok().unwrap(), "#42");
}
}