One step closer to functions

This commit is contained in:
Apache 2024-06-22 16:11:05 -05:00
parent 977c6b0e4e
commit 59bae011a3
Signed by: apache
GPG key ID: 6B10F3EAF14F4C77
3 changed files with 158 additions and 65 deletions

View file

@ -1,12 +1,14 @@
use std::{collections::HashMap, fmt}; use std::{collections::HashMap, fmt};
use crate::PreLispValue;
#[cfg(test)] #[cfg(test)]
mod tests { mod tests {
use crate::{parse, LispState, LispValue, Tokenizer, TokenizerError}; use crate::{parse, LispState, LispValue, Tokenizer};
use super::add_function; use super::add_function;
fn get_exec_result(source: &str) -> Result<Vec<LispValue>, TokenizerError> { fn get_exec_result(source: &str) -> Result<Vec<LispValue>, Box<dyn std::error::Error>> {
let mut state = LispState::new(); let mut state = LispState::new();
state.table.insert(String::from("output"), LispValue::List(vec![], false)); state.table.insert(String::from("output"), LispValue::List(vec![], false));
@ -15,13 +17,13 @@ mod tests {
v.push(LispValue::List(args, false)) v.push(LispValue::List(args, false))
} }
vec![LispValue::Nil] Ok(vec![LispValue::Nil])
}); });
let mut tokenizer = Tokenizer::new(String::from(source)); let mut tokenizer = Tokenizer::new(String::from(source));
let instructions = parse(tokenizer.tokenize()?); let instructions = parse(tokenizer.tokenize()?);
state.execute(instructions); state.execute(instructions)?;
let mut out = Vec::new(); let mut out = Vec::new();
if let LispValue::List(outerlist, _) = &state.table["output"] { if let LispValue::List(outerlist, _) = &state.table["output"] {
@ -38,7 +40,7 @@ mod tests {
} }
#[test] #[test]
fn test_hello_world() -> Result<(), TokenizerError> { fn test_hello_world() -> Result<(), Box<dyn std::error::Error>> {
assert_eq!( assert_eq!(
vec![ vec![
LispValue::String(String::from("Hello, World!")) LispValue::String(String::from("Hello, World!"))
@ -51,7 +53,7 @@ mod tests {
} }
#[test] #[test]
fn test_math() -> Result<(), TokenizerError> { fn test_math() -> Result<(), Box<dyn std::error::Error>> {
assert_eq!( assert_eq!(
vec![ vec![
LispValue::Float(16.05) LispValue::Float(16.05)
@ -72,16 +74,26 @@ mod tests {
} }
} }
use crate::PreLispValue;
pub struct LispState { pub struct LispState {
table: HashMap<String, LispValue>, table: HashMap<String, LispValue>,
} }
fn add_function<T: Into<String> + Clone>(table: &mut HashMap<String, LispValue>, name: T, func: fn(&mut LispState, Vec<LispValue>) -> Vec<LispValue>) {
table.insert(name.clone().into(), LispValue::RustFunction(name.into(), func)); #[derive(Debug)]
pub struct RuntimeError {
message: String,
} }
impl fmt::Display for RuntimeError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "Runtime Error: {}", self.message)
}
}
impl std::error::Error for RuntimeError {}
type RustFunctionType = fn(&mut LispState, Vec<LispValue>) -> Result<Vec<LispValue>, RuntimeError>;
#[derive(Debug, Clone, PartialEq)] #[derive(Debug, Clone, PartialEq)]
pub enum LispValue { pub enum LispValue {
Nil, Nil,
@ -89,8 +101,9 @@ pub enum LispValue {
Integer(i32), Integer(i32),
Float(f32), Float(f32),
List(Vec<LispValue>, bool), List(Vec<LispValue>, bool),
LispFunction(String, Vec<LispValue>), LispFunction(String, Vec<String>, Vec<LispValue>),
RustFunction(String, fn(&mut LispState, Vec<LispValue>) -> Vec<LispValue>), RustFunction(String, RustFunctionType),
Var(String)
} }
impl fmt::Display for LispValue { impl fmt::Display for LispValue {
@ -99,7 +112,7 @@ impl fmt::Display for LispValue {
match self { match self {
LispValue::Nil => write!(f, "nil"), LispValue::Nil => write!(f, "nil"),
LispValue::String(str) => write!(f, "\"{}\"", str), LispValue::String(str) => write!(f, "\"{}\"", str),
LispValue::LispFunction(name, _) => write!(f, "<function {}>", name), LispValue::LispFunction(name, _, _) => write!(f, "<function {}>", name),
LispValue::RustFunction(name, _) => write!(f, "<function {}>", name), LispValue::RustFunction(name, _) => write!(f, "<function {}>", name),
LispValue::Integer(num) => write!(f, "{}", num), LispValue::Integer(num) => write!(f, "{}", num),
LispValue::Float(num) => write!(f, "{}", num), LispValue::Float(num) => write!(f, "{}", num),
@ -123,6 +136,19 @@ impl fmt::Display for LispValue {
} }
} }
fn get_type(v: &LispValue) -> String {
match v {
LispValue::Nil => String::from("nil"),
LispValue::Integer(_) => String::from("int"),
LispValue::Float(_) => String::from("float"),
LispValue::String(_) => String::from("string"),
LispValue::List(_, _) => String::from("list"),
LispValue::LispFunction(_, _, _) => String::from("function"),
LispValue::RustFunction(_, _) => String::from("function"),
LispValue::Var(_) => String::from("symbol")
}
}
impl From<&str> for LispValue { impl From<&str> for LispValue {
fn from(value: &str) -> Self { fn from(value: &str) -> Self {
LispValue::String(value.to_string()) LispValue::String(value.to_string())
@ -143,6 +169,15 @@ impl From<f32> for LispValue {
LispValue::Float(value) LispValue::Float(value)
} }
} }
impl From<Vec<LispValue>> for LispValue {
fn from(value: Vec<LispValue>) -> Self {
LispValue::List(value, false)
}
}
fn add_function<T: Into<String> + Clone>(table: &mut HashMap<String, LispValue>, name: T, func: RustFunctionType) {
table.insert(name.clone().into(), LispValue::RustFunction(name.into(), func));
}
impl LispState { impl LispState {
pub fn new() -> LispState { pub fn new() -> LispState {
@ -157,7 +192,7 @@ impl LispState {
let str = strings.join(" "); let str = strings.join(" ");
println!("{}", str); println!("{}", str);
vec![LispValue::Nil] Ok(vec![LispValue::Nil])
}); });
add_function(&mut table, "concat", |_, args| { add_function(&mut table, "concat", |_, args| {
@ -167,14 +202,14 @@ impl LispState {
} }
let str = strings.concat(); let str = strings.concat();
vec![LispValue::String(str)] Ok(vec![LispValue::String(str)])
}); });
add_function(&mut table, "add", |_, args| { add_function(&mut table, "add", |_, args| {
if args.len() < 1 { if args.len() < 1 {
return vec![LispValue::Nil] return Ok(vec![LispValue::Nil])
} else if args.len() == 1 { } else if args.len() == 1 {
return vec![args[0].clone()]; return Ok(vec![args[0].clone()]);
} }
let mut t = "int"; let mut t = "int";
@ -182,7 +217,9 @@ impl LispState {
match v { match v {
LispValue::Float(_) => t = "float", LispValue::Float(_) => t = "float",
LispValue::Integer(_) => (), LispValue::Integer(_) => (),
_ => return vec![LispValue::Nil] _ => return Err(RuntimeError {
message: format!("Invalid argument to 'add' (expected float or int, got {}", get_type(v))
})
} }
} }
@ -196,7 +233,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Integer(sum)]; return Ok(vec![LispValue::Integer(sum)]);
}, },
"float" => { "float" => {
let mut sum = 0.0 as f32; let mut sum = 0.0 as f32;
@ -209,7 +246,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Float(sum)]; return Ok(vec![LispValue::Float(sum)]);
}, },
_ => unreachable!() _ => unreachable!()
} }
@ -217,9 +254,9 @@ impl LispState {
add_function(&mut table, "sub", |_, args| { add_function(&mut table, "sub", |_, args| {
if args.len() < 1 { if args.len() < 1 {
return vec![LispValue::Nil] return Ok(vec![LispValue::Nil]);
} else if args.len() == 1 { } else if args.len() == 1 {
return vec![args[0].clone()]; return Ok(vec![args[0].clone()]);
} }
let mut t = "int"; let mut t = "int";
@ -227,7 +264,9 @@ impl LispState {
match v { match v {
LispValue::Float(_) => t = "float", LispValue::Float(_) => t = "float",
LispValue::Integer(_) => (), LispValue::Integer(_) => (),
_ => return vec![LispValue::Nil] _ => return Err(RuntimeError {
message: format!("Invalid argument to 'sub' (expected float or int, got {}", get_type(v))
})
} }
} }
@ -242,7 +281,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Integer(sum)]; return Ok(vec![LispValue::Integer(sum)]);
} else { } else {
unreachable!() unreachable!()
} }
@ -259,7 +298,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Float(sum)]; return Ok(vec![LispValue::Float(sum)]);
} else if let LispValue::Integer(n) = args[0] { } else if let LispValue::Integer(n) = args[0] {
let mut sum = n as f32; let mut sum = n as f32;
for i in 1..args.len() { for i in 1..args.len() {
@ -271,7 +310,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Float(sum)]; return Ok(vec![LispValue::Float(sum)]);
} { } {
unreachable!() unreachable!()
} }
@ -282,9 +321,9 @@ impl LispState {
add_function(&mut table, "mul", |_, args| { add_function(&mut table, "mul", |_, args| {
if args.len() < 1 { if args.len() < 1 {
return vec![LispValue::Nil] return Ok(vec![LispValue::Nil]);
} else if args.len() == 1 { } else if args.len() == 1 {
return vec![args[0].clone()]; return Ok(vec![args[0].clone()]);
} }
let mut t = "int"; let mut t = "int";
@ -292,7 +331,9 @@ impl LispState {
match v { match v {
LispValue::Float(_) => t = "float", LispValue::Float(_) => t = "float",
LispValue::Integer(_) => (), LispValue::Integer(_) => (),
_ => return vec![LispValue::Nil] _ => return Err(RuntimeError {
message: format!("Invalid argument to 'mul' (expected float or int, got {}", get_type(v))
})
} }
} }
@ -307,7 +348,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Integer(sum)]; return Ok(vec![LispValue::Integer(sum)]);
} else { } else {
unreachable!() unreachable!()
} }
@ -324,7 +365,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Float(product)]; return Ok(vec![LispValue::Float(product)]);
} else if let LispValue::Integer(n) = args[0] { } else if let LispValue::Integer(n) = args[0] {
let mut product = n as f32; let mut product = n as f32;
for i in 1..args.len() { for i in 1..args.len() {
@ -336,7 +377,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Float(product)]; return Ok(vec![LispValue::Float(product)]);
} { } {
unreachable!() unreachable!()
} }
@ -347,9 +388,9 @@ impl LispState {
add_function(&mut table, "div", |_, args| { add_function(&mut table, "div", |_, args| {
if args.len() < 1 { if args.len() < 1 {
return vec![LispValue::Nil] return Ok(vec![LispValue::Nil]);
} else if args.len() == 1 { } else if args.len() == 1 {
return vec![args[0].clone()]; return Ok(vec![args[0].clone()]);
} }
let mut t = "int"; let mut t = "int";
@ -357,7 +398,9 @@ impl LispState {
match v { match v {
LispValue::Float(_) => t = "float", LispValue::Float(_) => t = "float",
LispValue::Integer(_) => (), LispValue::Integer(_) => (),
_ => return vec![LispValue::Nil] _ => return Err(RuntimeError {
message: format!("Invalid argument to 'div' (expected float or int, got {}", get_type(v))
})
} }
} }
@ -372,7 +415,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Integer(sum)]; return Ok(vec![LispValue::Integer(sum)]);
} else { } else {
unreachable!() unreachable!()
} }
@ -389,7 +432,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Float(product)]; return Ok(vec![LispValue::Float(product)]);
} else if let LispValue::Integer(n) = args[0] { } else if let LispValue::Integer(n) = args[0] {
let mut product = n as f32; let mut product = n as f32;
for i in 1..args.len() { for i in 1..args.len() {
@ -401,7 +444,7 @@ impl LispState {
unreachable!() unreachable!()
} }
} }
return vec![LispValue::Float(product)]; return Ok(vec![LispValue::Float(product)]);
} { } {
unreachable!() unreachable!()
} }
@ -427,11 +470,11 @@ impl LispState {
PreLispValue::List(list, quoted) => { PreLispValue::List(list, quoted) => {
LispValue::List(Self::handle_prevalues(self, list), quoted) LispValue::List(Self::handle_prevalues(self, list), quoted)
}, },
PreLispValue::LispFunction(name, instructions) => { PreLispValue::LispFunction(name, arg_names, instructions) => {
LispValue::LispFunction(name, Self::handle_prevalues(self, instructions)) LispValue::LispFunction(name, arg_names, Self::handle_prevalues(self, instructions))
}, },
PreLispValue::Var(name) => { PreLispValue::Var(name) => {
self.table.get(&name).unwrap_or(&LispValue::Nil).to_owned() LispValue::Var(name)
} }
}) })
} }
@ -439,16 +482,19 @@ impl LispState {
out out
} }
fn eval_list(&mut self, list: &Vec<LispValue>, quoted: bool) -> (Vec<LispValue>, bool) { fn eval_list(&mut self, env: &mut HashMap<String, LispValue>, list: &Vec<LispValue>, quoted: bool) -> Result<(Vec<LispValue>, bool), RuntimeError> {
if list.len() < 1 { if list.len() < 1 {
return (vec![LispValue::List(Vec::new(), quoted)], false); return Ok((vec![LispValue::List(Vec::new(), quoted)], false));
} }
let list = &mut list.clone(); let list = &mut list.clone();
for i in 0..list.len() { for i in 0..list.len() {
if let LispValue::Var(name) = &list[i] {
list[i] = env.get(name).unwrap_or_else(|| self.table.get(name).unwrap_or(&LispValue::Nil)).to_owned();
}
if let LispValue::List(elements, quoted) = &list[i] { if let LispValue::List(elements, quoted) = &list[i] {
let (elems, astuple) = self.eval_list(elements, *quoted); if let Ok((elems, astuple)) = self.eval_list(env, elements, *quoted) {
if astuple { if astuple {
list[i] = elems.get(0).unwrap_or(&LispValue::Nil).to_owned(); list[i] = elems.get(0).unwrap_or(&LispValue::Nil).to_owned();
for j in 1..elems.len() { for j in 1..elems.len() {
@ -459,30 +505,75 @@ impl LispState {
} }
} }
} }
}
if quoted { if quoted {
return (list.to_vec(), false); return Ok((list.to_vec(), false));
} }
if let LispValue::RustFunction(_name, f) = &list[0] { if let LispValue::RustFunction(_name, f) = &list[0] {
(f(self, list[1..].to_vec()), true) Ok((f(self, list[1..].to_vec())?, true))
} else if let LispValue::LispFunction(_name, _) = &list[0] { } else if let LispValue::LispFunction(_name, _, _) = &list[0] {
(self.call_lisp_func(&list[0], list[1..].to_vec()), true) Ok((self.call_lisp_func(env, &list[0], list[1..].to_vec())?, true))
} else { } else {
(list.to_vec(), false) Ok((list.to_vec(), false))
} }
} }
fn call_lisp_func(&mut self, f: &LispValue, args: Vec<LispValue>) -> Vec<LispValue> { fn call_lisp_func(&mut self, env: &mut HashMap<String, LispValue>, f: &LispValue, args: Vec<LispValue>) -> Result<Vec<LispValue>, RuntimeError> {
todo!("Calling lisp function {} with args {:?}", f, args) let (arg_names, instructions) = match f {
LispValue::LispFunction(_, arg_names, i) => {
(arg_names, i)
},
_ => return Err(RuntimeError {
message: format!("Invalid argument to call_lisp_func (expected function, got {})", get_type(f))
})
};
for i in 0..arg_names.len() {
env.insert(arg_names[i].to_owned(), args.get(i).unwrap_or(&LispValue::Nil).to_owned());
} }
pub fn execute(&mut self, instructions: Vec<PreLispValue>) { let mut out = Vec::new();
for l in instructions {
if let LispValue::List(elements, quoted) = l {
let (values, astuple) = self.eval_list(env, &elements, *quoted)?;
if values.len() > 0 && values[0] != LispValue::Nil {
if astuple {
for v in values {
out.push(v);
}
} else {
out.push(values.into());
}
}
}
}
Ok(out)
}
pub fn execute(&mut self, instructions: Vec<PreLispValue>) -> Result<Vec<LispValue>, RuntimeError> {
let instructions = Self::handle_prevalues(self, instructions); let instructions = Self::handle_prevalues(self, instructions);
let mut outs = Vec::new();
let mut env = HashMap::new();
for val in instructions { for val in instructions {
if let LispValue::List(elements, quoted) = val { if let LispValue::List(elements, quoted) = val {
self.eval_list(&elements, quoted); let (vals, astuple) = self.eval_list(&mut env, &elements, quoted)?;
if astuple {
for val in vals {
outs.push(val);
}
} else {
outs.push(vals.into())
}
} else {
outs.push(val);
} }
} }
Ok(outs)
} }
} }

View file

@ -93,7 +93,7 @@ pub enum PreLispValue {
Integer(i32), Integer(i32),
Float(f32), Float(f32),
List(Vec<PreLispValue>, bool), // Values, Quoted List(Vec<PreLispValue>, bool), // Values, Quoted
LispFunction(String, Vec<PreLispValue>), LispFunction(String, Vec<String>, Vec<PreLispValue>),
} }
impl fmt::Display for PreLispValue { impl fmt::Display for PreLispValue {
@ -101,7 +101,7 @@ impl fmt::Display for PreLispValue {
match self { match self {
PreLispValue::Nil => write!(f, "nil"), PreLispValue::Nil => write!(f, "nil"),
PreLispValue::String(str) => write!(f, "{}", str), PreLispValue::String(str) => write!(f, "{}", str),
PreLispValue::LispFunction(name, _) => write!(f, "<'{}': Lisp Function>", name), PreLispValue::LispFunction(name, _, _) => write!(f, "<'{}': Lisp Function>", name),
PreLispValue::Integer(num) => write!(f, "{}", num), PreLispValue::Integer(num) => write!(f, "{}", num),
PreLispValue::Float(num) => write!(f, "{}", num), PreLispValue::Float(num) => write!(f, "{}", num),
_ => todo!() _ => todo!()

View file

@ -118,6 +118,8 @@ impl fmt::Display for TokenizerError {
} }
} }
impl std::error::Error for TokenizerError {}
pub struct Tokenizer { pub struct Tokenizer {
code: String, code: String,
line: u64, line: u64,