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use super::*;
impl<'st> Interpreter {
pub fn handle_loop(&mut self, label: &Option<String>, body: &Expr) -> Result<Value, String> {
loop {
match self.evaluate_expression(body)? {
break_value if matches!(break_value.borrow().inner(), ValueType::Return(_)) => {
return Ok(break_value);
}
break_value if matches!(break_value.borrow().inner(), ValueType::Break(_, _)) => {
let (break_label, value) = if let ValueType::Break(label, value) = break_value.borrow().inner() {
(label, value)
} else {
unreachable!()
};
match (label, &break_label) {
(Some(loop_label), Some(break_label)) if loop_label == break_label => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(None, None) => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(_, Some(_)) => return Ok(break_value),
(Some(_), None) => return Ok(break_value),
}
}
continue_value if matches!(continue_value.borrow().inner(), ValueType::Continue(_)) => {
let continue_label = if let ValueType::Continue(label) = continue_value.borrow().inner() {
label
} else {
unreachable!()
};
match (label, &continue_label) {
(Some(loop_label), Some(continue_label)) if loop_label == continue_label => continue,
(None, None) => continue,
(_, Some(_)) => return Ok(continue_value),
(Some(_), None) => continue,
}
}
_ => continue,
}
}
}
pub fn handle_while(&mut self, label: &Option<String>, condition: &WhileCondition, body: &Expr) -> Result<Value, String> {
loop {
let should_execute = match condition {
WhileCondition::Expression(expr) => {
let cond_value = self.evaluate_expression(expr)?;
if let ValueType::Boolean(b) = cond_value.borrow().inner() {
b
} else {
return Err("While condition must evaluate to a boolean".to_string());
}
}
WhileCondition::Let(pattern, expr) => {
let value = self.evaluate_expression(expr)?;
self.env.enter_scope();
match self.declare_pattern(pattern, None, &value, true) {
Ok(_) => true,
Err(_) => {
self.env.exit_scope();
false
}
}
}
};
if !should_execute {
break;
}
match self.evaluate_expression(body)? {
break_value if matches!(break_value.borrow().inner(), ValueType::Return(_)) => {
if let WhileCondition::Let(..) = condition {
self.env.exit_scope();
}
return Ok(break_value);
}
break_value if matches!(break_value.borrow().inner(), ValueType::Break(_, _)) => {
if let WhileCondition::Let(..) = condition {
self.env.exit_scope();
}
let (break_label, value) = if let ValueType::Break(label, value) = break_value.borrow().inner() {
(label, value)
} else {
unreachable!()
};
match (label, &break_label) {
(Some(loop_label), Some(break_label)) if loop_label == break_label => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(None, None) => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(_, Some(_)) => return Ok(break_value),
(Some(_), None) => return Ok(break_value),
}
}
continue_value if matches!(continue_value.borrow().inner(), ValueType::Continue(_)) => {
if let WhileCondition::Let(..) = condition {
self.env.exit_scope();
}
let continue_label = if let ValueType::Continue(label) = continue_value.borrow().inner() {
label
} else {
unreachable!()
};
match (label, &continue_label) {
(Some(loop_label), Some(continue_label)) if loop_label == continue_label => continue,
(None, None) => continue,
(_, Some(_)) => return Ok(continue_value),
(Some(_), None) => continue,
}
}
_ => {
if let WhileCondition::Let(..) = condition {
self.env.exit_scope();
}
continue;
}
}
}
Ok(val!(ValueType::Unit))
}
pub fn handle_for(&mut self, label: &Option<String>, pattern: &Pattern, iterable: &Expr, body: &Expr) -> Result<Value, String> {
let iter_value = self.evaluate_expression(iterable)?;
match iter_value.borrow().inner() {
ValueType::Array { ref el, .. } => {
for item in el {
self.env.enter_scope();
self.declare_pattern(pattern, None, item, true)?;
match self.evaluate_expression(body)? {
break_value if matches!(break_value.borrow().inner(), ValueType::Return(_)) => {
self.env.exit_scope();
return Ok(break_value);
}
break_value if matches!(break_value.borrow().inner(), ValueType::Break(_, _)) => {
self.env.exit_scope();
let (break_label, value) = if let ValueType::Break(label, value) = break_value.borrow().inner() {
(label, value)
} else {
unreachable!()
};
match (label, &break_label) {
(Some(loop_label), Some(break_label)) if loop_label == break_label => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(None, None) => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(_, Some(_)) => return Ok(break_value),
(Some(_), None) => return Ok(break_value),
}
}
continue_value if matches!(continue_value.borrow().inner(), ValueType::Continue(_)) => {
self.env.exit_scope();
let continue_label = if let ValueType::Continue(label) = continue_value.borrow().inner() {
label
} else {
unreachable!()
};
match (label, &continue_label) {
(Some(loop_label), Some(continue_label)) if loop_label == continue_label => continue,
(None, None) => continue,
(_, Some(_)) => return Ok(continue_value),
(Some(_), None) => continue,
}
}
_ => {
self.env.exit_scope();
continue;
}
}
}
}
ValueType::Range { start, end, inclusive } => {
let start_val = start.borrow().inner();
let end_val = end.borrow().inner();
macro_rules! handle_range {
($s:expr, $e:expr, $variant:ident) => {{
let s = match $s {
Some(val) => val,
None => 0,
};
match $e {
None => {
let mut i = 0;
loop {
self.env.enter_scope();
self.declare_pattern(pattern, None, &val!(ValueType::$variant(s + i)), true)?;
match self.evaluate_expression(body)? {
break_value if matches!(break_value.borrow().inner(), ValueType::Return(_)) => {
self.env.exit_scope();
return Ok(break_value);
}
break_value if matches!(break_value.borrow().inner(), ValueType::Break(_, _)) => {
self.env.exit_scope();
let (break_label, value) = if let ValueType::Break(label, value) = break_value.borrow().inner() {
(label, value)
} else {
unreachable!()
};
match (label, &break_label) {
(Some(loop_label), Some(break_label)) if loop_label == break_label => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(None, None) => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(_, Some(_)) => return Ok(break_value),
(Some(_), None) => return Ok(break_value),
}
}
continue_value if matches!(continue_value.borrow().inner(), ValueType::Continue(_)) => {
self.env.exit_scope();
let continue_label = if let ValueType::Continue(label) = continue_value.borrow().inner() {
label
} else {
unreachable!()
};
match (label, &continue_label) {
(Some(loop_label), Some(continue_label)) if loop_label == continue_label => {
i += 1;
continue;
}
(None, None) => {
i += 1;
continue;
}
(_, Some(_)) => return Ok(continue_value),
(Some(_), None) => {
i += 1;
continue;
}
}
}
_ => {
self.env.exit_scope();
i += 1;
continue;
}
}
}
}
Some(e) => {
for i in s..if inclusive { e + 1 } else { e } {
self.env.enter_scope();
self.declare_pattern(pattern, None, &val!(ValueType::$variant(i)), true)?;
match self.evaluate_expression(body)? {
break_value if matches!(break_value.borrow().inner(), ValueType::Return(_)) => {
self.env.exit_scope();
return Ok(break_value);
}
break_value if matches!(break_value.borrow().inner(), ValueType::Break(_, _)) => {
self.env.exit_scope();
let (break_label, value) = if let ValueType::Break(label, value) = break_value.borrow().inner() {
(label, value)
} else {
unreachable!()
};
match (label, &break_label) {
(Some(loop_label), Some(break_label)) if loop_label == break_label => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(None, None) => {
return Ok(value.unwrap_or_else(|| val!(ValueType::Unit)));
}
(_, Some(_)) => return Ok(break_value),
(Some(_), None) => return Ok(break_value),
}
}
continue_value if matches!(continue_value.borrow().inner(), ValueType::Continue(_)) => {
self.env.exit_scope();
let continue_label = if let ValueType::Continue(label) = continue_value.borrow().inner() {
label
} else {
unreachable!()
};
match (label, &continue_label) {
(Some(loop_label), Some(continue_label)) if loop_label == continue_label => continue,
(None, None) => continue,
(_, Some(_)) => return Ok(continue_value),
(Some(_), None) => continue,
}
}
_ => {
self.env.exit_scope();
continue;
}
}
}
}
}
}};
}
match (start_val, end_val) {
(ValueType::Unbounded, ValueType::I8(e)) => handle_range!(None, Some(e), I8),
(ValueType::I8(s), ValueType::I8(e)) => handle_range!(Some(s), Some(e), I8),
(ValueType::Unbounded, ValueType::I16(e)) => handle_range!(None, Some(e), I16),
(ValueType::I16(s), ValueType::I16(e)) => handle_range!(Some(s), Some(e), I16),
(ValueType::Unbounded, ValueType::I32(e)) => handle_range!(None, Some(e), I32),
(ValueType::I32(s), ValueType::I32(e)) => handle_range!(Some(s), Some(e), I32),
(ValueType::Unbounded, ValueType::I64(e)) => handle_range!(None, Some(e), I64),
(ValueType::I64(s), ValueType::I64(e)) => handle_range!(Some(s), Some(e), I64),
(ValueType::Unbounded, ValueType::I128(e)) => handle_range!(None, Some(e), I128),
(ValueType::I128(s), ValueType::I128(e)) => handle_range!(Some(s), Some(e), I128),
(ValueType::Unbounded, ValueType::ISize(e)) => handle_range!(None, Some(e), ISize),
(ValueType::ISize(s), ValueType::ISize(e)) => handle_range!(Some(s), Some(e), ISize),
(ValueType::Unbounded, ValueType::U8(e)) => handle_range!(None, Some(e), U8),
(ValueType::U8(s), ValueType::U8(e)) => handle_range!(Some(s), Some(e), U8),
(ValueType::Unbounded, ValueType::U16(e)) => handle_range!(None, Some(e), U16),
(ValueType::U16(s), ValueType::U16(e)) => handle_range!(Some(s), Some(e), U16),
(ValueType::Unbounded, ValueType::U32(e)) => handle_range!(None, Some(e), U32),
(ValueType::U32(s), ValueType::U32(e)) => handle_range!(Some(s), Some(e), U32),
(ValueType::Unbounded, ValueType::U64(e)) => handle_range!(None, Some(e), U64),
(ValueType::U64(s), ValueType::U64(e)) => handle_range!(Some(s), Some(e), U64),
(ValueType::Unbounded, ValueType::U128(e)) => handle_range!(None, Some(e), U128),
(ValueType::U128(s), ValueType::U128(e)) => handle_range!(Some(s), Some(e), U128),
(ValueType::Unbounded, ValueType::USize(e)) => handle_range!(None, Some(e), USize),
(ValueType::USize(s), ValueType::USize(e)) => handle_range!(Some(s), Some(e), USize),
_ => return Err("Invalid range type".to_string()),
}
}
_ => return Err("Expression is not iterable".to_string()),
}
Ok(val!(ValueType::Unit))
}
}