forked from M-Labs/nac3
added expression inference
This commit is contained in:
parent
f1b8e73703
commit
e625bd4ad2
385
nac3core/src/expression.rs
Normal file
385
nac3core/src/expression.rs
Normal file
@ -0,0 +1,385 @@
|
||||
use crate::inference::resolve_call;
|
||||
use crate::operators::*;
|
||||
use crate::primitives::*;
|
||||
use crate::typedef::{GlobalContext, Type, Type::*};
|
||||
use rustpython_parser::ast::{
|
||||
Comparison, Comprehension, ComprehensionKind, Expression, ExpressionType, Operator,
|
||||
UnaryOperator,
|
||||
};
|
||||
use std::collections::HashMap;
|
||||
use std::convert::TryInto;
|
||||
use std::rc::Rc;
|
||||
|
||||
type SymTable<'a> = HashMap<&'a str, Rc<Type>>;
|
||||
type ParserResult = Result<Option<Rc<Type>>, String>;
|
||||
|
||||
pub fn infer_expr(ctx: &GlobalContext, sym_table: &SymTable, expr: &Expression) -> ParserResult {
|
||||
match &expr.node {
|
||||
ExpressionType::Number { value } => infer_constant(ctx, sym_table, value),
|
||||
ExpressionType::Identifier { name } => infer_identifier(ctx, sym_table, name),
|
||||
ExpressionType::List { elements } => infer_list(ctx, sym_table, elements),
|
||||
ExpressionType::Tuple { elements } => infer_tuple(ctx, sym_table, elements),
|
||||
ExpressionType::Attribute { value, name } => infer_attribute(ctx, sym_table, value, name),
|
||||
ExpressionType::BoolOp { values, .. } => infer_bool_ops(ctx, sym_table, values),
|
||||
ExpressionType::Binop { a, b, op } => infer_bin_ops(ctx, sym_table, op, a, b),
|
||||
ExpressionType::Unop { op, a } => infer_unary_ops(ctx, sym_table, op, a),
|
||||
ExpressionType::Compare { vals, ops } => infer_compare(ctx, sym_table, vals, ops),
|
||||
ExpressionType::Call {
|
||||
args,
|
||||
function,
|
||||
keywords,
|
||||
} => {
|
||||
if keywords.len() > 0 {
|
||||
Err("keyword is not supported".into())
|
||||
} else {
|
||||
infer_call(ctx, sym_table, &args, &function)
|
||||
}
|
||||
}
|
||||
ExpressionType::Subscript { a, b } => infer_subscript(ctx, sym_table, a, b),
|
||||
ExpressionType::IfExpression { test, body, orelse } => {
|
||||
infer_if_expr(ctx, sym_table, &test, &body, orelse)
|
||||
}
|
||||
ExpressionType::Comprehension { kind, generators } => match kind.as_ref() {
|
||||
ComprehensionKind::List { element } => {
|
||||
if generators.len() == 1 {
|
||||
infer_list_comprehension(ctx, sym_table, element, &generators[0])
|
||||
} else {
|
||||
Err("only 1 generator statement is supported".into())
|
||||
}
|
||||
}
|
||||
_ => Err("only list comprehension is supported".into()),
|
||||
},
|
||||
ExpressionType::True | ExpressionType::False => Ok(Some(PrimitiveType(BOOL_TYPE).into())),
|
||||
_ => Err("not supported".into()),
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_constant(
|
||||
_: &GlobalContext,
|
||||
_: &SymTable,
|
||||
value: &rustpython_parser::ast::Number,
|
||||
) -> ParserResult {
|
||||
use rustpython_parser::ast::Number;
|
||||
match value {
|
||||
Number::Integer { value } => {
|
||||
let int32: Result<i32, _> = value.try_into();
|
||||
if int32.is_ok() {
|
||||
Ok(Some(PrimitiveType(INT32_TYPE).into()))
|
||||
} else {
|
||||
let int64: Result<i64, _> = value.try_into();
|
||||
if int64.is_ok() {
|
||||
Ok(Some(PrimitiveType(INT64_TYPE).into()))
|
||||
} else {
|
||||
Err("integer out of range".into())
|
||||
}
|
||||
}
|
||||
}
|
||||
Number::Float { .. } => Ok(Some(PrimitiveType(FLOAT_TYPE).into())),
|
||||
_ => Err("not supported".into()),
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_identifier(_: &GlobalContext, sym_table: &SymTable, name: &str) -> ParserResult {
|
||||
match sym_table.get(name) {
|
||||
Some(v) => Ok(Some(v.clone())),
|
||||
None => Err("unbounded variable".into()),
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_list(ctx: &GlobalContext, sym_table: &SymTable, elements: &[Expression]) -> ParserResult {
|
||||
if elements.len() == 0 {
|
||||
return Ok(Some(ParametricType(LIST_TYPE, vec![BotType.into()]).into()));
|
||||
}
|
||||
|
||||
let mut types = elements.iter().map(|v| infer_expr(&ctx, sym_table, v));
|
||||
|
||||
let head = types.next().unwrap()?;
|
||||
if head.is_none() {
|
||||
return Err("list elements must have some type".into());
|
||||
}
|
||||
for v in types {
|
||||
if v? != head {
|
||||
return Err("inhomogeneous list is not allowed".into());
|
||||
}
|
||||
}
|
||||
Ok(Some(ParametricType(LIST_TYPE, vec![head.unwrap()]).into()))
|
||||
}
|
||||
|
||||
fn infer_tuple(ctx: &GlobalContext, sym_table: &SymTable, elements: &[Expression]) -> ParserResult {
|
||||
let types: Result<Option<Vec<_>>, String> = elements
|
||||
.iter()
|
||||
.map(|v| infer_expr(&ctx, sym_table, v))
|
||||
.collect();
|
||||
if let Some(t) = types? {
|
||||
Ok(Some(ParametricType(TUPLE_TYPE, t).into()))
|
||||
} else {
|
||||
Err("tuple elements must have some type".into())
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_attribute(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
value: &Expression,
|
||||
name: &String,
|
||||
) -> ParserResult {
|
||||
let value = infer_expr(ctx, sym_table, value)?.ok_or("no value".to_string())?;
|
||||
if let TypeVariable(id) = value.as_ref() {
|
||||
let v = ctx.get_variable(*id);
|
||||
if v.bound.len() == 0 {
|
||||
return Err("no fields on unbounded type variable".into());
|
||||
}
|
||||
let ty = v.bound[0]
|
||||
.get_base(ctx)
|
||||
.and_then(|v| v.fields.get(name.as_str()));
|
||||
if ty.is_none() {
|
||||
return Err("unknown field".into());
|
||||
}
|
||||
for x in v.bound[1..].iter() {
|
||||
let ty1 = x.get_base(ctx).and_then(|v| v.fields.get(name.as_str()));
|
||||
if ty1 != ty {
|
||||
return Err("unknown field (type mismatch between variants)".into());
|
||||
}
|
||||
}
|
||||
return Ok(Some(ty.unwrap().clone()));
|
||||
}
|
||||
|
||||
match value.get_base(ctx) {
|
||||
Some(b) => match b.fields.get(name.as_str()) {
|
||||
Some(t) => Ok(Some(t.clone())),
|
||||
None => Err("no such field".into()),
|
||||
},
|
||||
None => Err("this object has no fields".into()),
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_bool_ops(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
values: &[Expression],
|
||||
) -> ParserResult {
|
||||
assert_eq!(values.len(), 2);
|
||||
let left = infer_expr(ctx, sym_table, &values[0])?.ok_or("no value".to_string())?;
|
||||
let right = infer_expr(ctx, sym_table, &values[1])?.ok_or("no value".to_string())?;
|
||||
|
||||
let b = PrimitiveType(BOOL_TYPE);
|
||||
if left.as_ref() == &b && right.as_ref() == &b {
|
||||
Ok(Some(b.into()))
|
||||
} else {
|
||||
Err("bool operands must be bool".into())
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_bin_ops(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
op: &Operator,
|
||||
left: &Expression,
|
||||
right: &Expression,
|
||||
) -> ParserResult {
|
||||
let left = infer_expr(ctx, sym_table, left)?.ok_or("no value".to_string())?;
|
||||
let right = infer_expr(ctx, sym_table, right)?.ok_or("no value".to_string())?;
|
||||
let fun = binop_name(op);
|
||||
resolve_call(ctx, Some(left), fun, &[right])
|
||||
}
|
||||
|
||||
fn infer_unary_ops(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
op: &UnaryOperator,
|
||||
obj: &Expression,
|
||||
) -> ParserResult {
|
||||
let ty = infer_expr(ctx, sym_table, obj)?.ok_or("no value".to_string())?;
|
||||
if let UnaryOperator::Not = op {
|
||||
if ty.as_ref() == &PrimitiveType(BOOL_TYPE) {
|
||||
Ok(Some(ty))
|
||||
} else {
|
||||
Err("logical not must be applied to bool".into())
|
||||
}
|
||||
} else {
|
||||
resolve_call(ctx, Some(ty), unaryop_name(op), &[])
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_compare(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
vals: &[Expression],
|
||||
ops: &[Comparison],
|
||||
) -> ParserResult {
|
||||
let types: Result<Option<Vec<_>>, _> =
|
||||
vals.iter().map(|v| infer_expr(ctx, sym_table, v)).collect();
|
||||
let types = types?;
|
||||
if types.is_none() {
|
||||
return Err("comparison operands must have type".into());
|
||||
}
|
||||
let types = types.unwrap();
|
||||
let boolean = PrimitiveType(BOOL_TYPE);
|
||||
let left = &types[..types.len() - 1];
|
||||
let right = &types[1..];
|
||||
|
||||
for ((a, b), op) in left.iter().zip(right.iter()).zip(ops.iter()) {
|
||||
let fun = comparison_name(op).ok_or("unsupported comparison".to_string())?;
|
||||
let ty = resolve_call(ctx, Some(a.clone()), fun, &[b.clone()])?;
|
||||
if ty.is_none() || ty.unwrap().as_ref() != &boolean {
|
||||
return Err("comparison result must be boolean".into());
|
||||
}
|
||||
}
|
||||
Ok(Some(boolean.into()))
|
||||
}
|
||||
|
||||
fn infer_call(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
args: &[Expression],
|
||||
function: &Expression,
|
||||
) -> ParserResult {
|
||||
let types: Result<Option<Vec<_>>, _> =
|
||||
args.iter().map(|v| infer_expr(ctx, sym_table, v)).collect();
|
||||
let types = types?;
|
||||
if types.is_none() {
|
||||
return Err("function params must have type".into());
|
||||
}
|
||||
|
||||
let (obj, fun) = match &function.node {
|
||||
ExpressionType::Identifier { name } => (None, name),
|
||||
ExpressionType::Attribute { value, name } => (
|
||||
Some(infer_expr(ctx, sym_table, &value)?.ok_or("no value".to_string())?),
|
||||
name,
|
||||
),
|
||||
_ => return Err("not supported".into()),
|
||||
};
|
||||
resolve_call(ctx, obj, fun.as_str(), &types.unwrap())
|
||||
}
|
||||
|
||||
fn infer_subscript(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
a: &Expression,
|
||||
b: &Expression,
|
||||
) -> ParserResult {
|
||||
let a = infer_expr(ctx, sym_table, a)?.ok_or("no value".to_string())?;
|
||||
let t = if let ParametricType(LIST_TYPE, ls) = a.as_ref() {
|
||||
ls[0].clone()
|
||||
} else {
|
||||
return Err("subscript is not supported for types other than list".into());
|
||||
};
|
||||
|
||||
match &b.node {
|
||||
ExpressionType::Slice { elements } => {
|
||||
let int32 = Rc::new(PrimitiveType(INT32_TYPE));
|
||||
let types: Result<Option<Vec<_>>, _> = elements
|
||||
.iter()
|
||||
.map(|v| {
|
||||
if let ExpressionType::None = v.node {
|
||||
Ok(Some(int32.clone()))
|
||||
} else {
|
||||
infer_expr(ctx, sym_table, v)
|
||||
}
|
||||
})
|
||||
.collect();
|
||||
let types = types?.ok_or("slice must have type".to_string())?;
|
||||
if types.iter().all(|v| v == &int32) {
|
||||
Ok(Some(a))
|
||||
} else {
|
||||
Err("slice must be int32 type".into())
|
||||
}
|
||||
}
|
||||
_ => {
|
||||
let b = infer_expr(ctx, sym_table, b)?.ok_or("no value".to_string())?;
|
||||
if b.as_ref() == &PrimitiveType(INT32_TYPE) {
|
||||
Ok(Some(t))
|
||||
} else {
|
||||
Err("index must be either slice or int32".into())
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_if_expr(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
test: &Expression,
|
||||
body: &Expression,
|
||||
orelse: &Expression,
|
||||
) -> ParserResult {
|
||||
let test = infer_expr(ctx, sym_table, test)?.ok_or("no value".to_string())?;
|
||||
if test.as_ref() != &PrimitiveType(BOOL_TYPE) {
|
||||
return Err("test should be bool".into());
|
||||
}
|
||||
|
||||
let body = infer_expr(ctx, sym_table, body)?;
|
||||
let orelse = infer_expr(ctx, sym_table, orelse)?;
|
||||
if body.as_ref() == orelse.as_ref() {
|
||||
Ok(body)
|
||||
} else {
|
||||
Err("divergent type".into())
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_simple_binding<'a: 'b, 'b>(
|
||||
sym_table: &mut SymTable<'b>,
|
||||
name: &'a Expression,
|
||||
ty: Rc<Type>,
|
||||
) -> Result<(), String> {
|
||||
match &name.node {
|
||||
ExpressionType::Identifier { name } => {
|
||||
if name == "_" {
|
||||
Ok(())
|
||||
} else if sym_table.get(name.as_str()).is_some() {
|
||||
Err("duplicated naming".into())
|
||||
} else {
|
||||
sym_table.insert(name.as_str(), ty);
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
ExpressionType::Tuple { elements } => {
|
||||
if let ParametricType(TUPLE_TYPE, ls) = ty.as_ref() {
|
||||
if elements.len() == ls.len() {
|
||||
for (a, b) in elements.iter().zip(ls.iter()) {
|
||||
infer_simple_binding(sym_table, a, b.clone())?;
|
||||
}
|
||||
Ok(())
|
||||
} else {
|
||||
Err("different length".into())
|
||||
}
|
||||
} else {
|
||||
Err("not supported".into())
|
||||
}
|
||||
}
|
||||
_ => Err("not supported".into()),
|
||||
}
|
||||
}
|
||||
|
||||
fn infer_list_comprehension(
|
||||
ctx: &GlobalContext,
|
||||
sym_table: &SymTable,
|
||||
element: &Expression,
|
||||
comprehension: &Comprehension,
|
||||
) -> ParserResult {
|
||||
if comprehension.is_async {
|
||||
return Err("async is not supported".into());
|
||||
}
|
||||
|
||||
// TODO: it may be more efficient to use multi-level table
|
||||
// but it would better done in a whole program level
|
||||
let iter = infer_expr(ctx, sym_table, &comprehension.iter)?.ok_or("no value".to_string())?;
|
||||
if let ParametricType(LIST_TYPE, ls) = iter.as_ref() {
|
||||
let mut local_sym = sym_table.clone();
|
||||
infer_simple_binding(&mut local_sym, &comprehension.target, ls[0].clone())?;
|
||||
|
||||
let boolean = PrimitiveType(BOOL_TYPE);
|
||||
for test in comprehension.ifs.iter() {
|
||||
let result =
|
||||
infer_expr(ctx, &local_sym, test)?.ok_or("no value in test".to_string())?;
|
||||
if result.as_ref() != &boolean {
|
||||
return Err("test must be bool".into());
|
||||
}
|
||||
}
|
||||
let result = infer_expr(ctx, &local_sym, element)?.ok_or("no value")?;
|
||||
Ok(Some(ParametricType(LIST_TYPE, vec![result]).into()))
|
||||
} else {
|
||||
Err("iteration is supported for list only".into())
|
||||
}
|
||||
}
|
||||
|
||||
@ -2,6 +2,7 @@ extern crate num_bigint;
|
||||
extern crate inkwell;
|
||||
extern crate rustpython_parser;
|
||||
|
||||
pub mod expression;
|
||||
pub mod inference;
|
||||
mod operators;
|
||||
pub mod primitives;
|
||||
|
||||
Loading…
Reference in New Issue
Block a user