Move command parsers into parsers module

This commit is contained in:
Lewis Dale 2023-01-21 08:40:11 +00:00
parent 92e98bbdcb
commit ed885b0f81
3 changed files with 68 additions and 62 deletions

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@ -1,11 +1,8 @@
use std::collections::HashMap;
use nom::{
branch::alt, bytes::complete::tag, character::complete::u64 as ccu64, combinator::map,
multi::separated_list0, sequence::terminated, IResult,
};
use nom::{bytes::complete::tag, multi::separated_list0, IResult};
use crate::parsers::{generic, variables};
use crate::parsers::commands;
pub type Line = (usize, Command);
@ -115,11 +112,22 @@ impl Program {
};
}
}
fn read(i: &str) -> IResult<&str, Self> {
let (i, lines) = separated_list0(tag("\n"), commands::parse_line)(i)?;
let mut node = Node::None;
for line in lines.iter() {
node.push(line.clone());
}
Ok((i, Program::new(node)))
}
}
impl From<&str> for Program {
fn from(value: &str) -> Self {
let (_, program) = read_program(value).unwrap();
let (_, program) = Self::read(value).unwrap();
program
}
}
@ -139,65 +147,13 @@ impl Iterator for Program {
}
}
fn match_command(i: &str) -> IResult<&str, &str> {
alt((tag("PRINT"), tag("GO TO"), tag("LET"), tag("REM")))(i)
}
fn parse_print_command(i: &str) -> IResult<&str, PrintOutput> {
alt((
map(
alt((
variables::parse_str_variable_name,
variables::parse_int_variable_name,
)),
PrintOutput::Variable,
),
map(generic::read_string, PrintOutput::Value),
))(i)
}
fn parse_command(i: &str) -> IResult<&str, Command> {
let (i, command): (&str, &str) = match_command(i).unwrap_or((i, ""));
let (i, _) = tag(" ")(i)?;
let (i, cmd) = match command {
"PRINT" => map(parse_print_command, Command::Print)(i)?,
"GO TO" => map(ccu64, |line| Command::GoTo(line as usize))(i)?,
"LET" => map(variables::parse_var, Command::Var)(i)?,
"REM" => {
let (i, _) = generic::consume_line(i)?;
(i, Command::Comment)
}
_ => (i, Command::None),
};
Ok((i, cmd))
}
pub fn parse_line(line: &str) -> IResult<&str, Line> {
let (i, line_number) = map(terminated(ccu64, tag(" ")), |l| l as usize)(line)?;
let (i, command) = parse_command(i)?;
Ok((i, (line_number, command)))
}
pub fn read_program(i: &str) -> IResult<&str, Program> {
let (i, lines) = separated_list0(tag("\n"), parse_line)(i)?;
let mut node = Node::None;
for line in lines.iter() {
node.push(line.clone());
}
Ok((i, Program::new(node)))
}
#[cfg(test)]
mod tests {
use crate::basic::PrintOutput;
use super::{parse_line, read_program, Command, Line, Node, Primitive};
use super::{Command, Line, Node, Primitive, Program};
use crate::parsers::generic::read_string;
use crate::parsers::{commands::parse_line, generic::read_string};
#[test]
fn it_parses_a_print_command() {
@ -308,8 +264,8 @@ mod tests {
next: Box::new(Node::None),
}),
};
let expected = ("", super::Program::new(expected_node));
let result = read_program(lines).unwrap();
let expected = Program::new(expected_node);
let result = Program::from(lines);
assert_eq!(expected, result);
}

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@ -1,2 +1,3 @@
pub mod commands;
pub mod generic;
pub mod variables;

49
src/parsers/commands.rs Normal file
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@ -0,0 +1,49 @@
use nom::{
branch::alt, bytes::complete::tag, character::complete::u64 as ccu64, combinator::map,
sequence::terminated, IResult,
};
use crate::basic::{Command, Line, PrintOutput};
use super::{generic, variables};
pub fn match_command(i: &str) -> IResult<&str, &str> {
alt((tag("PRINT"), tag("GO TO"), tag("LET"), tag("REM")))(i)
}
pub fn parse_print_command(i: &str) -> IResult<&str, PrintOutput> {
alt((
map(
alt((
variables::parse_str_variable_name,
variables::parse_int_variable_name,
)),
PrintOutput::Variable,
),
map(generic::read_string, PrintOutput::Value),
))(i)
}
pub fn parse_command(i: &str) -> IResult<&str, Command> {
let (i, command): (&str, &str) = match_command(i).unwrap_or((i, ""));
let (i, _) = tag(" ")(i)?;
let (i, cmd) = match command {
"PRINT" => map(parse_print_command, Command::Print)(i)?,
"GO TO" => map(ccu64, |line| Command::GoTo(line as usize))(i)?,
"LET" => map(variables::parse_var, Command::Var)(i)?,
"REM" => {
let (i, _) = generic::consume_line(i)?;
(i, Command::Comment)
}
_ => (i, Command::None),
};
Ok((i, cmd))
}
pub fn parse_line(line: &str) -> IResult<&str, Line> {
let (i, line_number) = map(terminated(ccu64, tag(" ")), |l| l as usize)(line)?;
let (i, command) = parse_command(i)?;
Ok((i, (line_number, command)))
}