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extern crate lalrpop_util;
extern crate colored;
extern crate regex;
pub mod parser;
pub mod ast;
use colored::*;
use lalrpop_util::ParseError;
use regex::Regex;
pub fn strip_comments(raw: &str) -> String {
// TODO: shouldn't recompile regex on every function call
// Match on comments:
// (?m) sets multi-line mode
let comment_re = Regex::new(r"(?m)(//.*)$").unwrap();
comment_re.replace_all(&raw, "")
}
fn pp_segment(raw: &str, start: usize, end: usize) -> String {
let mut line_start = 0;
let mut num = 0;
let mut ret = String::new();
for line in raw.lines() {
num += 1;
let line_end = line_start + line.len();
if (line_start <= start) && (start < line_end) {
ret += &format!(" {}\n{:>3} {} {}{}{}\n {} {}{}\n",
"|".blue().bold(),
num.to_string().blue().bold(),
"|".blue().bold(),
raw[line_start..start].normal(),
raw[start..end].red().bold(),
if end < line_end {
raw[end..line_end].normal()
} else {
"".normal()
},
"|".blue().bold(),
std::iter::repeat(" ").take(start - line_start).collect::<String>(),
std::iter::repeat("^").take(end - start).collect::<String>().red().bold());
}
line_start += line.len() + 1;
if line_start > end { break };
}
ret
}
pub fn pp_parseerror(raw: &str, pe: ParseError<usize, (usize, &str), ()>) -> String {
match pe {
ParseError::InvalidToken{location} => {
format!("{} invalid token starting at:\n{}",
"parse error:".red().bold(),
pp_segment(raw, location, location+1)) },
ParseError::UnrecognizedToken{token: Some((start, (_, tok), end)), expected} => {
format!("{} unrecognized token '{}'{}:\n{}",
"parse error:".red().bold(),
tok,
if expected.len() > 0 {
format!(" (expected one of {:?})", expected)
} else {
format!("")
},
pp_segment(raw, start, end)) },
ParseError::UnrecognizedToken{token: None, expected} => {
format!("{} premature end-of-file{}",
"parse error:".red().bold(),
if expected.len() > 0 {
format!(" (expected one of {:?})", expected)
} else {
format!("")
}) },
ParseError::ExtraToken{token: (start, (_, tok), end)} => {
format!("{} unexpected extra token '{}':\n{}",
"parse error:".red().bold(),
tok,
pp_segment(raw, start, end)) },
_ => {
format!("{} {:?}", "parse error:".red().bold(), pe) },
}
}
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