Implement capturing.

This commit is contained in:
Stephen Chung
2020-07-30 18:18:28 +08:00
parent e505a06839
commit 98b294c699
17 changed files with 410 additions and 180 deletions

View File

@@ -748,12 +748,12 @@ pub enum Expr {
Stmt(Box<(Stmt, Position)>),
/// Wrapped expression - should not be optimized away.
Expr(Box<Expr>),
/// func(expr, ... ) - ((function name, native_only, position), optional modules, hash, arguments, optional default value)
/// func(expr, ... ) - ((function name, native_only, capture, position), optional modules, hash, arguments, optional default value)
/// Use `Cow<'static, str>` because a lot of operators (e.g. `==`, `>=`) are implemented as function calls
/// and the function names are predictable, so no need to allocate a new `String`.
FnCall(
Box<(
(Cow<'static, str>, bool, Position),
(Cow<'static, str>, bool, bool, Position),
Option<Box<ModuleRef>>,
u64,
StaticVec<Expr>,
@@ -871,7 +871,7 @@ impl Expr {
Self::Property(x) => x.1,
Self::Stmt(x) => x.1,
Self::Variable(x) => (x.0).1,
Self::FnCall(x) => (x.0).2,
Self::FnCall(x) => (x.0).3,
Self::Assignment(x) => x.0.position(),
Self::And(x) | Self::Or(x) | Self::In(x) => x.2,
@@ -903,7 +903,7 @@ impl Expr {
Self::Variable(x) => (x.0).1 = new_pos,
Self::Property(x) => x.1 = new_pos,
Self::Stmt(x) => x.1 = new_pos,
Self::FnCall(x) => (x.0).2 = new_pos,
Self::FnCall(x) => (x.0).3 = new_pos,
Self::And(x) => x.2 = new_pos,
Self::Or(x) => x.2 = new_pos,
Self::In(x) => x.2 = new_pos,
@@ -1009,6 +1009,7 @@ impl Expr {
#[cfg(not(feature = "no_index"))]
Token::LeftBracket => true,
Token::LeftParen => true,
Token::Bang => true,
Token::DoubleColon => true,
_ => false,
},
@@ -1101,6 +1102,7 @@ fn parse_fn_call(
state: &mut ParseState,
lib: &mut FunctionsLib,
id: String,
capture: bool,
mut modules: Option<Box<ModuleRef>>,
settings: ParseSettings,
) -> Result<Expr, ParseError> {
@@ -1143,7 +1145,7 @@ fn parse_fn_call(
};
return Ok(Expr::FnCall(Box::new((
(id.into(), false, settings.pos),
(id.into(), false, capture, settings.pos),
modules,
hash_script,
args,
@@ -1185,7 +1187,7 @@ fn parse_fn_call(
};
return Ok(Expr::FnCall(Box::new((
(id.into(), false, settings.pos),
(id.into(), false, capture, settings.pos),
modules,
hash_script,
args,
@@ -1594,6 +1596,8 @@ fn parse_primary(
_ => input.next().unwrap(),
};
let (next_token, _) = input.peek().unwrap();
let mut root_expr = match token {
Token::IntegerConstant(x) => Expr::IntegerConstant(Box::new((x, settings.pos))),
#[cfg(not(feature = "no_float"))]
@@ -1605,7 +1609,7 @@ fn parse_primary(
Expr::Variable(Box::new(((s, settings.pos), None, 0, index)))
}
// Function call is allowed to have reserved keyword
Token::Reserved(s) if input.peek().unwrap().0 == Token::LeftParen => {
Token::Reserved(s) if *next_token == Token::LeftParen || *next_token == Token::Bang => {
if is_keyword_function(&s) {
Expr::Variable(Box::new(((s, settings.pos), None, 0, None)))
} else {
@@ -1613,7 +1617,7 @@ fn parse_primary(
}
}
// Access to `this` as a variable is OK
Token::Reserved(s) if s == KEYWORD_THIS && input.peek().unwrap().0 != Token::LeftParen => {
Token::Reserved(s) if s == KEYWORD_THIS && *next_token != Token::LeftParen => {
if !settings.is_function_scope {
return Err(
PERR::BadInput(format!("'{}' can only be used in functions", s))
@@ -1653,11 +1657,26 @@ fn parse_primary(
settings.pos = token_pos;
root_expr = match (root_expr, token) {
// Function call
#[cfg(not(feature = "no_capture"))]
(Expr::Variable(x), Token::Bang) => {
if !match_token(input, Token::LeftParen)? {
return Err(PERR::MissingToken(
Token::LeftParen.syntax().into(),
"to start arguments list of function call".into(),
)
.into_err(input.peek().unwrap().1));
}
let ((name, pos), modules, _, _) = *x;
settings.pos = pos;
parse_fn_call(input, state, lib, name, true, modules, settings.level_up())?
}
// Function call
(Expr::Variable(x), Token::LeftParen) => {
let ((name, pos), modules, _, _) = *x;
settings.pos = pos;
parse_fn_call(input, state, lib, name, modules, settings.level_up())?
parse_fn_call(input, state, lib, name, false, modules, settings.level_up())?
}
(Expr::Property(_), _) => unreachable!(),
// module access
@@ -1767,7 +1786,7 @@ fn parse_unary(
args.push(expr);
Ok(Expr::FnCall(Box::new((
(op.into(), true, pos),
(op.into(), true, false, pos),
None,
hash,
args,
@@ -1792,7 +1811,7 @@ fn parse_unary(
let hash = calc_fn_hash(empty(), op, 2, empty());
Ok(Expr::FnCall(Box::new((
(op.into(), true, pos),
(op.into(), true, false, pos),
None,
hash,
args,
@@ -1987,7 +2006,14 @@ fn make_dot_expr(lhs: Expr, rhs: Expr, op_pos: Position) -> Result<Expr, ParseEr
op_pos,
)))
}
// lhs.func()
// lhs.func!(...)
(_, Expr::FnCall(x)) if (x.0).2 => {
return Err(PERR::MalformedCapture(
"method-call style does not support capturing".into(),
)
.into_err((x.0).3))
}
// lhs.func(...)
(lhs, func @ Expr::FnCall(_)) => Expr::Dot(Box::new((lhs, func, op_pos))),
// lhs.rhs
(_, rhs) => return Err(PERR::PropertyExpected.into_err(rhs.position())),
@@ -2196,7 +2222,7 @@ fn parse_binary_op(
let cmp_def = Some(false);
let op = op_token.syntax();
let hash = calc_fn_hash(empty(), &op, 2, empty());
let op = (op, true, pos);
let op = (op, true, false, pos);
let mut args = StaticVec::new();
args.push(root);
@@ -2257,7 +2283,7 @@ fn parse_binary_op(
.unwrap_or(false) =>
{
// Accept non-native functions for custom operators
let op = (op.0, false, op.2);
let op = (op.0, false, op.2, op.3);
Expr::FnCall(Box::new((op, None, hash, args, None)))
}
@@ -2975,10 +3001,12 @@ fn parse_fn(
let (token, pos) = input.next().unwrap();
let name = token.into_function_name().map_err(|t| match t {
Token::Reserved(s) => PERR::Reserved(s).into_err(pos),
_ => PERR::FnMissingName.into_err(pos),
})?;
let name = token
.into_function_name_for_override()
.map_err(|t| match t {
Token::Reserved(s) => PERR::Reserved(s).into_err(pos),
_ => PERR::FnMissingName.into_err(pos),
})?;
match input.peek().unwrap() {
(Token::LeftParen, _) => eat_token(input, Token::LeftParen),
@@ -3085,7 +3113,7 @@ fn make_curry_from_externals(
let hash = calc_fn_hash(empty(), KEYWORD_FN_PTR_CURRY, num_externals, empty());
let fn_call = Expr::FnCall(Box::new((
(KEYWORD_FN_PTR_CURRY.into(), false, pos),
(KEYWORD_FN_PTR_CURRY.into(), false, false, pos),
None,
hash,
args,