Решение на Basic BASIC от Андрей
Резултати
- 20 точки от тестове
- 0 бонус точки
- 20 точки общо
- 15 успешни тест(а)
- 0 неуспешни тест(а)
Код
use std::collections::HashMap;
use std::io::{Write, Read, BufReader, BufRead};
#[derive(Debug)]
pub enum InterpreterError {
RuntimeError { line_number: u16, message: String },
UnknownVariable { name: String },
NotANumber { value: String },
SyntaxError { code: String },
IoError(std::io::Error),
}
impl From<std::io::Error> for InterpreterError {
fn from(source: std::io::Error) -> Self {
Self::IoError(source)
}
}
#[derive(Debug)]
enum Statement {
Print { value: String },
Read { var_name: String },
Goto { line_number: u16 },
If { condition: String, line_number: u16 },
}
pub struct Interpreter<'a, R: Read, W: Write> {
code_lines: HashMap<u16, Statement>,
variables: HashMap<String, u16>,
input: BufReader<R>,
output: &'a mut W,
}
impl<'a, R: Read, W: Write> Interpreter<'a, R, W> {
pub fn new(input: R, output: &'a mut W) -> Self {
Self {
code_lines: HashMap::new(),
variables: HashMap::new(),
input: BufReader::new(input),
output,
}
}
pub fn add(&mut self, code: &str) -> Result<u16, InterpreterError> {
let (line_number, statement) = parse_code_line(code)?;
self.code_lines.insert(line_number, statement);
Ok(line_number)
}
pub fn run(&mut self) -> Result<(), InterpreterError> {
let mut line_numbers = self.code_lines.keys().cloned().collect::<Vec<_>>();
line_numbers.sort();
let Some(&(mut current_line_number)) = line_numbers.get(0) else {
return Ok(());
};
macro_rules! runtime_error {
($($arg:tt)*) => {
InterpreterError::RuntimeError {
line_number: current_line_number,
message: format!($($arg)*),
}
}
}
loop {
let statement = self.code_lines.get(¤t_line_number).unwrap();
match statement {
Statement::Print { value } => {
match self.eval_value(value) {
Ok(number) => writeln!(self.output, "{}", number)?,
Err(InterpreterError::UnknownVariable { name }) => {
return Err(runtime_error!("Unknown variable: {name}"));
},
_ => writeln!(self.output, "{}", value)?,
}
},
Statement::Read { var_name } => {
let mut user_input = String::new();
self.input.read_line(&mut user_input)?;
let user_input = user_input.trim();
let value = user_input.parse().
map_err(|_| runtime_error!("Not a number: {user_input}"))?;
self.variables.insert(var_name.clone(), value);
},
Statement::Goto { line_number } => {
if self.code_lines.contains_key(line_number) {
current_line_number = *line_number;
continue;
} else {
return Err(runtime_error!("Invalid line number for GOTO: {line_number}"));
}
},
Statement::If { condition, line_number } => {
let mut parts = condition.split_whitespace();
let left = self.eval_value(parts.next().unwrap()).
map_err(|e| runtime_error!("{:?}", e))?;
let op = parts.next().unwrap();
let right = self.eval_value(parts.next().unwrap()).
map_err(|e| runtime_error!("{:?}", e))?;
let result = match op {
">" => if left > right { 1 } else { 0 },
"<" => if left < right { 1 } else { 0 },
"=" => if left == right { 1 } else { 0 },
_ => unreachable!(),
};
if result > 0 {
if self.code_lines.contains_key(line_number) {
current_line_number = *line_number;
continue;
} else {
return Err(runtime_error!("Invalid line number for GOTO: {line_number}"));
}
}
},
}
let line_number_index = line_numbers.binary_search(¤t_line_number).
map_err(|_| runtime_error!("Couldn't find line number {current_line_number}"))?;
if let Some(line_number) = line_numbers.get(line_number_index + 1) {
current_line_number = *line_number;
} else {
break;
}
}
Ok(())
}
pub fn eval_value(&self, value: &str) -> Result<u16, InterpreterError> {
let first_char = value.chars().next().unwrap();
if first_char.is_uppercase() {
self.variables.get(value).
ok_or_else(|| InterpreterError::UnknownVariable { name: value.to_string() }).
map(|n| *n)
} else {
value.trim().parse().
map_err(|_| InterpreterError::NotANumber { value: value.to_string() })
}
}
}
fn parse_code_line(input: &str) -> Result<(u16, Statement), InterpreterError> {
macro_rules! syntax_error {
() => { InterpreterError::SyntaxError { code: input.to_owned() } }
}
let parts: Vec<&str> = input.split_whitespace().collect();
let line_number = parts.get(0).
ok_or_else(|| syntax_error!())?.
parse().
map_err(|_| syntax_error!())?;
let statement =
match parts.get(1) {
Some(&"PRINT") => {
let value = parts.get(2).ok_or_else(|| syntax_error!())?.to_string();
if parts.len() > 3 {
return Err(syntax_error!());
}
Statement::Print { value }
},
Some(&"READ") => {
let var_name = parts.get(2).ok_or_else(|| syntax_error!())?.to_string();
if !var_name.chars().next().unwrap().is_uppercase() {
return Err(syntax_error!());
}
if parts.len() > 3 {
return Err(syntax_error!());
}
Statement::Read { var_name }
},
Some(&"GOTO") => {
let line_number = parts.get(2).ok_or_else(|| syntax_error!())?.to_string().
parse().map_err(|_| syntax_error!())?;
if parts.len() > 3 {
return Err(syntax_error!());
}
Statement::Goto { line_number }
},
Some(&"IF") => {
let condition = parts[2..=4].join(" ");
if !matches!(parts.get(5), Some(&"GOTO")) {
return Err(syntax_error!());
}
let line_number = parts.get(6).ok_or_else(|| syntax_error!())?.to_string().
parse().map_err(|_| syntax_error!())?;
if parts.len() > 7 {
return Err(syntax_error!());
}
Statement::If { condition, line_number }
},
_ => { return Err(syntax_error!()) }
};
Ok((line_number, statement))
}
Лог от изпълнението
Compiling solution v0.1.0 (/tmp/d20230111-3772066-6867tg/solution)
Finished test [unoptimized + debuginfo] target(s) in 1.63s
Running tests/solution_test.rs (target/debug/deps/solution_test-0edbea2040daef01)
running 15 tests
test solution_test::test_basic_goto ... ok
test solution_test::test_basic_if ... ok
test solution_test::test_basic_input ... ok
test solution_test::test_basic_print ... ok
test solution_test::test_basic_read ... ok
test solution_test::test_erroring_goto ... ok
test solution_test::test_io_error_read ... ok
test solution_test::test_io_error_write ... ok
test solution_test::test_full_program ... ok
test solution_test::test_line_order_and_overwriting ... ok
test solution_test::test_print_vars_and_strings ... ok
test solution_test::test_print_cyrillic ... ok
test solution_test::test_syntax_errors_1 ... ok
test solution_test::test_runtime_errors ... ok
test solution_test::test_syntax_errors_2 ... ok
test result: ok. 15 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
История (2 версии и 0 коментара)
Андрей качи решение на 20.12.2022 11:12 (преди над 2 години)
use std::collections::HashMap;
use std::io::{Write, Read, BufReader, BufRead};
#[derive(Debug)]
pub enum InterpreterError {
RuntimeError { line_number: u16, message: String },
UnknownVariable { name: String },
NotANumber { value: String },
SyntaxError { code: String },
- NoProgram,
IoError(std::io::Error),
}
impl From<std::io::Error> for InterpreterError {
fn from(source: std::io::Error) -> Self {
Self::IoError(source)
}
}
#[derive(Debug)]
enum Statement {
Print { value: String },
Read { var_name: String },
Goto { line_number: u16 },
If { condition: String, line_number: u16 },
}
pub struct Interpreter<'a, R: Read, W: Write> {
code_lines: HashMap<u16, Statement>,
variables: HashMap<String, u16>,
input: BufReader<R>,
output: &'a mut W,
}
impl<'a, R: Read, W: Write> Interpreter<'a, R, W> {
pub fn new(input: R, output: &'a mut W) -> Self {
Self {
code_lines: HashMap::new(),
variables: HashMap::new(),
input: BufReader::new(input),
output,
}
}
pub fn add(&mut self, code: &str) -> Result<u16, InterpreterError> {
let (line_number, statement) = parse_code_line(code)?;
self.code_lines.insert(line_number, statement);
Ok(line_number)
}
pub fn run(&mut self) -> Result<(), InterpreterError> {
let mut line_numbers = self.code_lines.keys().cloned().collect::<Vec<_>>();
line_numbers.sort();
- let mut current_line_number = *line_numbers.get(0).
- ok_or_else(|| InterpreterError::NoProgram)?;
+
+ let Some(&(mut current_line_number)) = line_numbers.get(0) else {
+ return Ok(());
+ };
macro_rules! runtime_error {
($($arg:tt)*) => {
InterpreterError::RuntimeError {
line_number: current_line_number,
message: format!($($arg)*),
}
}
}
loop {
let statement = self.code_lines.get(¤t_line_number).unwrap();
match statement {
Statement::Print { value } => {
match self.eval_value(value) {
Ok(number) => writeln!(self.output, "{}", number)?,
Err(InterpreterError::UnknownVariable { name }) => {
return Err(runtime_error!("Unknown variable: {name}"));
},
_ => writeln!(self.output, "{}", value)?,
}
},
Statement::Read { var_name } => {
let mut user_input = String::new();
self.input.read_line(&mut user_input)?;
let user_input = user_input.trim();
let value = user_input.parse().
map_err(|_| runtime_error!("Not a number: {user_input}"))?;
self.variables.insert(var_name.clone(), value);
},
Statement::Goto { line_number } => {
if self.code_lines.contains_key(line_number) {
current_line_number = *line_number;
continue;
} else {
return Err(runtime_error!("Invalid line number for GOTO: {line_number}"));
}
},
Statement::If { condition, line_number } => {
let mut parts = condition.split_whitespace();
let left = self.eval_value(parts.next().unwrap()).
map_err(|e| runtime_error!("{:?}", e))?;
let op = parts.next().unwrap();
let right = self.eval_value(parts.next().unwrap()).
map_err(|e| runtime_error!("{:?}", e))?;
let result = match op {
">" => if left > right { 1 } else { 0 },
"<" => if left < right { 1 } else { 0 },
"=" => if left == right { 1 } else { 0 },
_ => unreachable!(),
};
if result > 0 {
if self.code_lines.contains_key(line_number) {
current_line_number = *line_number;
continue;
} else {
return Err(runtime_error!("Invalid line number for GOTO: {line_number}"));
}
}
},
}
let line_number_index = line_numbers.binary_search(¤t_line_number).
map_err(|_| runtime_error!("Couldn't find line number {current_line_number}"))?;
if let Some(line_number) = line_numbers.get(line_number_index + 1) {
current_line_number = *line_number;
} else {
break;
}
}
Ok(())
}
pub fn eval_value(&self, value: &str) -> Result<u16, InterpreterError> {
let first_char = value.chars().next().unwrap();
if first_char.is_uppercase() {
self.variables.get(value).
ok_or_else(|| InterpreterError::UnknownVariable { name: value.to_string() }).
map(|n| *n)
} else {
value.trim().parse().
map_err(|_| InterpreterError::NotANumber { value: value.to_string() })
}
}
}
fn parse_code_line(input: &str) -> Result<(u16, Statement), InterpreterError> {
macro_rules! syntax_error {
() => { InterpreterError::SyntaxError { code: input.to_owned() } }
}
let parts: Vec<&str> = input.split_whitespace().collect();
let line_number = parts.get(0).
ok_or_else(|| syntax_error!())?.
parse().
map_err(|_| syntax_error!())?;
let statement =
match parts.get(1) {
Some(&"PRINT") => {
let value = parts.get(2).ok_or_else(|| syntax_error!())?.to_string();
if parts.len() > 3 {
return Err(syntax_error!());
}
Statement::Print { value }
},
Some(&"READ") => {
let var_name = parts.get(2).ok_or_else(|| syntax_error!())?.to_string();
if !var_name.chars().next().unwrap().is_uppercase() {
return Err(syntax_error!());
}
if parts.len() > 3 {
return Err(syntax_error!());
}
Statement::Read { var_name }
},
Some(&"GOTO") => {
let line_number = parts.get(2).ok_or_else(|| syntax_error!())?.to_string().
parse().map_err(|_| syntax_error!())?;
if parts.len() > 3 {
return Err(syntax_error!());
}
Statement::Goto { line_number }
},
Some(&"IF") => {
let condition = parts[2..=4].join(" ");
if !matches!(parts.get(5), Some(&"GOTO")) {
return Err(syntax_error!());
}
let line_number = parts.get(6).ok_or_else(|| syntax_error!())?.to_string().
parse().map_err(|_| syntax_error!())?;
if parts.len() > 7 {
return Err(syntax_error!());
}
Statement::If { condition, line_number }
},
_ => { return Err(syntax_error!()) }
};
Ok((line_number, statement))
}