Implement evaluator materializer and CLI

This commit is contained in:
Keisuke Hirata 2026-06-16 02:10:54 +09:00
parent ddcee75c8d
commit c33c484bac
No known key found for this signature in database
6 changed files with 1082 additions and 11 deletions

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@ -1,3 +1,163 @@
fn main() {
println!("Decodal {}", decodal_core::version());
use std::{env, fs, process::ExitCode};
use decodal_core::{Data, Diagnostic, Engine, parse_source};
fn main() -> ExitCode {
match run() {
Ok(()) => ExitCode::SUCCESS,
Err(error) => {
print_diagnostic(&error);
ExitCode::FAILURE
}
}
}
fn run() -> Result<(), Diagnostic> {
let mut args = env::args().skip(1);
let first = args.next().unwrap_or_else(|| String::from("--help"));
match first.as_str() {
"--help" | "-h" => {
print_help();
Ok(())
}
"--version" | "-V" => {
println!("Decodal {}", decodal_core::version());
Ok(())
}
"check" => {
let path = args.next().unwrap_or_else(|| String::from("-"));
let source = read_source(&path)?;
let parsed = parse_source(&source)?;
let mut engine = Engine::from_parse(parsed.ast, parsed.root);
let value = engine.eval_root()?;
engine.materialize(&value)?;
println!("ok");
Ok(())
}
"eval" | "materialize" => {
let path = args.next().unwrap_or_else(|| String::from("-"));
materialize_file(&path)
}
path => materialize_file(path),
}
}
fn materialize_file(path: &str) -> Result<(), Diagnostic> {
let source = read_source(path)?;
let parsed = parse_source(&source)?;
let mut engine = Engine::from_parse(parsed.ast, parsed.root);
let value = engine.eval_root()?;
let data = engine.materialize(&value)?;
print_data(&data, 0);
println!();
Ok(())
}
fn read_source(path: &str) -> Result<String, Diagnostic> {
if path == "-" {
use std::io::Read;
let mut source = String::new();
std::io::stdin()
.read_to_string(&mut source)
.map_err(|error| {
Diagnostic::new(
decodal_core::DiagnosticKind::Import,
decodal_core::Span::default(),
format!("failed to read stdin: {error}"),
)
})?;
Ok(source)
} else {
fs::read_to_string(path).map_err(|error| {
Diagnostic::new(
decodal_core::DiagnosticKind::Import,
decodal_core::Span::default(),
format!("failed to read `{path}`: {error}"),
)
})
}
}
fn print_help() {
println!("Decodal - Deferred Constraint Data Language");
println!();
println!("Usage:");
println!(" decodal <file.dcdl> Materialize a DCDL file");
println!(" decodal eval <file.dcdl> Materialize a DCDL file");
println!(" decodal check <file.dcdl> Evaluate and materialize without printing data");
println!(" decodal - Read DCDL source from stdin");
}
fn print_diagnostic(error: &Diagnostic) {
eprintln!(
"error[{kind:?}] {start}..{end}: {message}",
kind = error.kind,
start = error.span.start,
end = error.span.end,
message = error.message,
);
}
fn print_data(data: &Data, indent: usize) {
match data {
Data::String(value) => print_string(value),
Data::Int(value) => print!("{value}"),
Data::Float(value) => print!("{value}"),
Data::Bool(value) => print!("{value}"),
Data::Array(items) => {
print!("[");
if !items.is_empty() {
println!();
for (index, item) in items.iter().enumerate() {
print_indent(indent + 2);
print_data(item, indent + 2);
if index + 1 != items.len() {
print!(",");
}
println!();
}
print_indent(indent);
}
print!("]");
}
Data::Object(fields) => {
print!("{{");
if !fields.is_empty() {
println!();
for (index, field) in fields.iter().enumerate() {
print_indent(indent + 2);
print_string(&field.name);
print!(": ");
print_data(&field.value, indent + 2);
if index + 1 != fields.len() {
print!(",");
}
println!();
}
print_indent(indent);
}
print!("}}");
}
}
}
fn print_indent(indent: usize) {
for _ in 0..indent {
print!(" ");
}
}
fn print_string(value: &str) {
print!("\"");
for ch in value.chars() {
match ch {
'"' => print!("\\\""),
'\\' => print!("\\\\"),
'\n' => print!("\\n"),
'\r' => print!("\\r"),
'\t' => print!("\\t"),
ch => print!("{ch}"),
}
}
print!("\"");
}

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@ -0,0 +1,772 @@
use alloc::{format, string::String, vec, vec::Vec};
use crate::{
Span,
ast::{Ast, BinaryOp, CompareOp, Expr, ExprId, Field, Literal},
diagnostic::{Diagnostic, DiagnosticKind, Result},
runtime::{
AbstractValue, Binding, ConcreteValue, Constraint, Data, DataField, Env, EnvId,
FunctionParam, FunctionValue, LiteralValue, ObjectField, ObjectValue, PrimitiveType,
RuntimeValue, Thunk, ThunkId, ThunkKind, ThunkState,
},
};
pub struct Engine {
ast: Ast,
root: ExprId,
thunks: Vec<Thunk>,
envs: Vec<Env>,
}
impl Engine {
pub fn from_parse(ast: Ast, root: ExprId) -> Self {
let mut this = Self {
ast,
root,
thunks: Vec::new(),
envs: Vec::new(),
};
this.envs.push(Env {
parent: None,
bindings: Vec::new(),
});
this
}
pub fn eval_root(&mut self) -> Result<RuntimeValue> {
self.eval_expr(self.root, EnvId(0))
}
pub fn materialize(&mut self, value: &RuntimeValue) -> Result<Data> {
match value {
RuntimeValue::Concrete(value) => match value {
ConcreteValue::String(value) => Ok(Data::String(value.clone())),
ConcreteValue::Int(value) => Ok(Data::Int(*value)),
ConcreteValue::Float(value) => Ok(Data::Float(*value)),
ConcreteValue::Bool(value) => Ok(Data::Bool(*value)),
ConcreteValue::Array(items) => {
let mut data = Vec::new();
for item in items {
let value = self.force(*item)?;
data.push(self.materialize(&value)?);
}
Ok(Data::Array(data))
}
ConcreteValue::Object(object) => {
let mut fields = Vec::new();
for field in &object.fields {
let value = self.force(field.value)?;
fields.push(DataField {
name: field.name.clone(),
value: self.materialize(&value)?,
});
}
Ok(Data::Object(fields))
}
ConcreteValue::Function(_) => Err(Diagnostic::new(
DiagnosticKind::Materialize,
Span::default(),
"cannot materialize function value",
)),
},
RuntimeValue::Abstract(abstract_value) => {
let Some(default) = abstract_value.default else {
return Err(Diagnostic::new(
DiagnosticKind::Materialize,
Span::default(),
"cannot materialize unresolved abstract value without default",
));
};
let value = self.force(default)?;
self.ensure_satisfies(&value, &abstract_value.constraints, Span::default())?;
self.materialize(&value)
}
}
}
fn eval_expr(&mut self, id: ExprId, env: EnvId) -> Result<RuntimeValue> {
let span = self.ast.span(id);
let expr = self.ast.get(id).expr.clone();
match expr {
Expr::Literal(literal) => Ok(RuntimeValue::Concrete(literal_to_concrete(literal))),
Expr::Ident(name) => self.eval_ident(&name, env, span),
Expr::Object(fields) => self.eval_object(&fields, env),
Expr::Array(items) => {
let thunks = items
.into_iter()
.map(|item| self.add_expr_thunk(item, env))
.collect();
Ok(RuntimeValue::Concrete(ConcreteValue::Array(thunks)))
}
Expr::Let { bindings, body } => {
let let_env = self.new_child_env(env);
for binding in bindings {
let name = field_name(&binding)?;
let thunk = self.add_expr_thunk(binding.value, let_env);
self.bind(let_env, name, thunk);
}
self.eval_expr(body, let_env)
}
Expr::Import(_) => Err(Diagnostic::new(
DiagnosticKind::UnsupportedFeature,
span,
"import evaluation is not implemented yet",
)),
Expr::Path { base, field } => {
let base = self.eval_expr(base, env)?;
let RuntimeValue::Concrete(ConcreteValue::Object(object)) = base else {
return Err(Diagnostic::new(
DiagnosticKind::TypeMismatch,
span,
"path base is not an object",
));
};
let Some(thunk) = object
.fields
.iter()
.find(|item| item.name == field)
.map(|item| item.value)
else {
return Err(Diagnostic::new(
DiagnosticKind::UnresolvedIdentifier,
span,
format!("unknown field `{field}`"),
));
};
self.force(thunk)
}
Expr::Call { callee, args } => self.eval_call(callee, args, env, span),
Expr::Function { params, body } => {
let params = params
.into_iter()
.map(|param| FunctionParam {
name: param.name,
constraint: param.constraint,
})
.collect();
Ok(RuntimeValue::Concrete(ConcreteValue::Function(
FunctionValue { params, body, env },
)))
}
Expr::Match { scrutinee, arms } => {
let value = self.eval_expr(scrutinee, env)?;
for arm in arms {
if self.matches_pattern(&value, arm.pattern, env)? {
return self.eval_expr(arm.body, env);
}
}
Err(Diagnostic::new(
DiagnosticKind::MatchFailure,
span,
"no match arm matched",
))
}
Expr::Binary { op, lhs, rhs } => {
let lhs = self.eval_expr(lhs, env)?;
let rhs = self.eval_expr(rhs, env)?;
match op {
BinaryOp::And => self.compose_and(lhs, rhs, span),
BinaryOp::Patch => self.patch(lhs, rhs),
}
}
Expr::Default { base, fallback } => {
let base = self.eval_expr(base, env)?;
match base {
RuntimeValue::Abstract(mut abstract_value) => {
abstract_value.default = Some(self.add_expr_thunk(fallback, env));
Ok(RuntimeValue::Abstract(abstract_value))
}
concrete @ RuntimeValue::Concrete(_) => Ok(concrete),
}
}
Expr::CompareConstraint { op, value } => {
let value = self.eval_expr(value, env)?;
let value = literal_value_from_runtime(&value).ok_or_else(|| {
Diagnostic::new(
DiagnosticKind::TypeMismatch,
span,
"comparison constraint operand must be a literal",
)
})?;
Ok(RuntimeValue::Abstract(AbstractValue {
constraints: vec![Constraint::Compare(op, value)],
default: None,
}))
}
Expr::RegexConstraint(pattern) => Ok(RuntimeValue::Abstract(AbstractValue {
constraints: vec![Constraint::Regex(pattern)],
default: None,
})),
Expr::Wildcard => Err(Diagnostic::new(
DiagnosticKind::UnsupportedFeature,
span,
"wildcard is only valid as a match pattern",
)),
}
}
fn eval_ident(&mut self, name: &str, env: EnvId, span: Span) -> Result<RuntimeValue> {
if let Some(primitive) = primitive_type(name) {
return Ok(RuntimeValue::Abstract(AbstractValue {
constraints: vec![Constraint::Type(primitive)],
default: None,
}));
}
if let Some(thunk) = self.lookup(env, name) {
return self.force(thunk);
}
if name.chars().next().is_some_and(char::is_uppercase) {
return Ok(RuntimeValue::Abstract(AbstractValue {
constraints: vec![Constraint::BuiltinPredicate(String::from(name))],
default: None,
}));
}
Err(Diagnostic::new(
DiagnosticKind::UnresolvedIdentifier,
span,
format!("unknown identifier `{name}`"),
))
}
fn eval_object(&mut self, fields: &[Field], env: EnvId) -> Result<RuntimeValue> {
let mut object = ObjectValue { fields: Vec::new() };
for field in fields {
self.insert_field(&mut object, &field.path, field.value, env, field.span)?;
}
Ok(RuntimeValue::Concrete(ConcreteValue::Object(object)))
}
fn insert_field(
&mut self,
object: &mut ObjectValue,
path: &[String],
expr: ExprId,
env: EnvId,
span: Span,
) -> Result<()> {
if path.is_empty() {
return Err(Diagnostic::new(
DiagnosticKind::Syntax,
span,
"empty field path",
));
}
if path.len() == 1 {
let value = self.add_expr_thunk(expr, env);
if object.fields.iter().any(|field| field.name == path[0]) {
return Err(Diagnostic::new(
DiagnosticKind::Conflict,
span,
format!("duplicate field `{}`", path[0]),
));
}
object.fields.push(ObjectField {
name: path[0].clone(),
value,
});
return Ok(());
}
let name = &path[0];
if let Some(index) = object.fields.iter().position(|field| field.name == *name) {
let existing = self.force(object.fields[index].value)?;
let RuntimeValue::Concrete(ConcreteValue::Object(mut nested)) = existing else {
return Err(Diagnostic::new(
DiagnosticKind::Conflict,
span,
format!("field `{name}` is already defined as a non-object"),
));
};
self.insert_field(&mut nested, &path[1..], expr, env, span)?;
object.fields[index].value =
self.add_value_thunk(RuntimeValue::Concrete(ConcreteValue::Object(nested)));
return Ok(());
}
let mut nested = ObjectValue { fields: Vec::new() };
self.insert_field(&mut nested, &path[1..], expr, env, span)?;
object.fields.push(ObjectField {
name: name.clone(),
value: self.add_value_thunk(RuntimeValue::Concrete(ConcreteValue::Object(nested))),
});
Ok(())
}
fn eval_call(
&mut self,
callee: ExprId,
args: Vec<ExprId>,
caller_env: EnvId,
span: Span,
) -> Result<RuntimeValue> {
let callee = self.eval_expr(callee, caller_env)?;
let RuntimeValue::Concrete(ConcreteValue::Function(function)) = callee else {
return Err(Diagnostic::new(
DiagnosticKind::TypeMismatch,
span,
"callee is not a function",
));
};
if args.len() != function.params.len() {
return Err(Diagnostic::new(
DiagnosticKind::TypeMismatch,
span,
"function call argument count mismatch",
));
}
let call_env = self.new_child_env(function.env);
for (param, arg) in function.params.iter().zip(args) {
let arg_thunk = if let Some(constraint) = param.constraint {
self.add_constrained_thunk(constraint, function.env, arg, caller_env)
} else {
self.add_expr_thunk(arg, caller_env)
};
self.bind(call_env, param.name.clone(), arg_thunk);
}
self.eval_expr(function.body, call_env)
}
fn matches_pattern(
&mut self,
value: &RuntimeValue,
pattern: ExprId,
env: EnvId,
) -> Result<bool> {
match self.ast.get(pattern).expr.clone() {
Expr::Wildcard => Ok(true),
Expr::CompareConstraint { .. } | Expr::RegexConstraint(_) | Expr::Ident(_) => {
let constraint = self.eval_expr(pattern, env)?;
match constraint {
RuntimeValue::Abstract(abstract_value) => self
.ensure_satisfies(
value,
&abstract_value.constraints,
self.ast.span(pattern),
)
.map(|_| true)
.or_else(|diag| match diag.kind {
DiagnosticKind::ConstraintViolation
| DiagnosticKind::UnsupportedFeature => Ok(false),
_ => Err(diag),
}),
other => Ok(&other == value),
}
}
_ => {
let pattern_value = self.eval_expr(pattern, env)?;
Ok(&pattern_value == value)
}
}
}
fn compose_and(
&mut self,
lhs: RuntimeValue,
rhs: RuntimeValue,
span: Span,
) -> Result<RuntimeValue> {
match (lhs, rhs) {
(RuntimeValue::Abstract(mut lhs), RuntimeValue::Abstract(rhs)) => {
lhs.constraints.extend(rhs.constraints);
lhs.default = merge_default(lhs.default, rhs.default, span)?;
Ok(RuntimeValue::Abstract(lhs))
}
(RuntimeValue::Abstract(abstract_value), concrete @ RuntimeValue::Concrete(_))
| (concrete @ RuntimeValue::Concrete(_), RuntimeValue::Abstract(abstract_value)) => {
self.ensure_satisfies(&concrete, &abstract_value.constraints, span)?;
Ok(concrete)
}
(
RuntimeValue::Concrete(ConcreteValue::Object(lhs)),
RuntimeValue::Concrete(ConcreteValue::Object(rhs)),
) => self.compose_objects(lhs, rhs, span),
(RuntimeValue::Concrete(lhs), RuntimeValue::Concrete(rhs)) => {
if concrete_scalar_eq(&lhs, &rhs) {
Ok(RuntimeValue::Concrete(lhs))
} else {
Err(Diagnostic::new(
DiagnosticKind::Conflict,
span,
"concrete values conflict",
))
}
}
}
}
fn compose_objects(
&mut self,
mut lhs: ObjectValue,
rhs: ObjectValue,
span: Span,
) -> Result<RuntimeValue> {
for rhs_field in rhs.fields {
if let Some(index) = lhs
.fields
.iter()
.position(|lhs_field| lhs_field.name == rhs_field.name)
{
let lhs_value = self.force(lhs.fields[index].value)?;
let rhs_value = self.force(rhs_field.value)?;
let value = self.compose_and(lhs_value, rhs_value, span)?;
lhs.fields[index].value = self.add_value_thunk(value);
} else {
lhs.fields.push(rhs_field);
}
}
Ok(RuntimeValue::Concrete(ConcreteValue::Object(lhs)))
}
fn patch(&mut self, lhs: RuntimeValue, rhs: RuntimeValue) -> Result<RuntimeValue> {
match (lhs, rhs) {
(
RuntimeValue::Concrete(ConcreteValue::Object(lhs)),
RuntimeValue::Concrete(ConcreteValue::Object(rhs)),
) => self.patch_objects(lhs, rhs),
(_, rhs) => Ok(rhs),
}
}
fn patch_objects(&mut self, mut lhs: ObjectValue, rhs: ObjectValue) -> Result<RuntimeValue> {
for rhs_field in rhs.fields {
if let Some(index) = lhs
.fields
.iter()
.position(|lhs_field| lhs_field.name == rhs_field.name)
{
let lhs_value = self.force(lhs.fields[index].value)?;
let rhs_value = self.force(rhs_field.value)?;
let value = self.patch(lhs_value, rhs_value)?;
lhs.fields[index].value = self.add_value_thunk(value);
} else {
lhs.fields.push(rhs_field);
}
}
Ok(RuntimeValue::Concrete(ConcreteValue::Object(lhs)))
}
fn ensure_satisfies(
&mut self,
value: &RuntimeValue,
constraints: &[Constraint],
span: Span,
) -> Result<()> {
for constraint in constraints {
self.satisfies(value, constraint, span)?;
}
Ok(())
}
fn satisfies(
&mut self,
value: &RuntimeValue,
constraint: &Constraint,
span: Span,
) -> Result<()> {
match constraint {
Constraint::Type(primitive) => {
if value_matches_primitive(value, *primitive) {
Ok(())
} else {
Err(Diagnostic::new(
DiagnosticKind::ConstraintViolation,
span,
"value does not satisfy primitive type constraint",
))
}
}
Constraint::Compare(op, expected) => compare_value(value, *op, expected)
.then_some(())
.ok_or_else(|| {
Diagnostic::new(
DiagnosticKind::ConstraintViolation,
span,
"value does not satisfy comparison constraint",
)
}),
Constraint::Regex(_) => Err(Diagnostic::new(
DiagnosticKind::UnsupportedFeature,
span,
"regex constraints require a future regex feature",
)),
Constraint::BuiltinPredicate(name) => Err(Diagnostic::new(
DiagnosticKind::UnsupportedFeature,
span,
format!("builtin predicate `{name}` is not implemented"),
)),
}
}
fn force(&mut self, id: ThunkId) -> Result<RuntimeValue> {
let index = id.0 as usize;
match self.thunks[index].state.clone() {
ThunkState::Evaluated(value) => return Ok(value),
ThunkState::Evaluating => {
self.thunks[index].state = ThunkState::Error;
return Err(Diagnostic::new(
DiagnosticKind::Cycle,
Span::default(),
"cyclic thunk dependency",
));
}
ThunkState::Error => {
return Err(Diagnostic::new(
DiagnosticKind::Cycle,
Span::default(),
"thunk previously failed",
));
}
ThunkState::Unevaluated => {}
}
self.thunks[index].state = ThunkState::Evaluating;
let kind = self.thunks[index].kind.clone();
let result = match kind {
ThunkKind::Expr { expr, env } => self.eval_expr(expr, env),
ThunkKind::Constrained {
constraint,
constraint_env,
value,
value_env,
} => {
let span = self.ast.span(value);
let constraint = self.eval_expr(constraint, constraint_env)?;
let value = self.eval_expr(value, value_env)?;
self.compose_and(constraint, value, span)
}
ThunkKind::Value(value) => Ok(value),
};
match result {
Ok(value) => {
self.thunks[index].state = ThunkState::Evaluated(value.clone());
Ok(value)
}
Err(error) => {
self.thunks[index].state = ThunkState::Error;
Err(error)
}
}
}
fn add_expr_thunk(&mut self, expr: ExprId, env: EnvId) -> ThunkId {
self.add_thunk(ThunkKind::Expr { expr, env })
}
fn add_constrained_thunk(
&mut self,
constraint: ExprId,
constraint_env: EnvId,
value: ExprId,
value_env: EnvId,
) -> ThunkId {
self.add_thunk(ThunkKind::Constrained {
constraint,
constraint_env,
value,
value_env,
})
}
fn add_value_thunk(&mut self, value: RuntimeValue) -> ThunkId {
self.add_thunk(ThunkKind::Value(value))
}
fn add_thunk(&mut self, kind: ThunkKind) -> ThunkId {
let id = ThunkId(self.thunks.len() as u32);
self.thunks.push(Thunk {
kind,
state: ThunkState::Unevaluated,
});
id
}
fn new_child_env(&mut self, parent: EnvId) -> EnvId {
let id = EnvId(self.envs.len() as u32);
self.envs.push(Env {
parent: Some(parent),
bindings: Vec::new(),
});
id
}
fn bind(&mut self, env: EnvId, name: String, value: ThunkId) {
self.envs[env.0 as usize]
.bindings
.push(Binding { name, value });
}
fn lookup(&self, env: EnvId, name: &str) -> Option<ThunkId> {
let mut current = Some(env);
while let Some(env) = current {
let frame = &self.envs[env.0 as usize];
if let Some(binding) = frame
.bindings
.iter()
.rev()
.find(|binding| binding.name == name)
{
return Some(binding.value);
}
current = frame.parent;
}
None
}
}
fn field_name(field: &Field) -> Result<String> {
if field.path.len() == 1 {
Ok(field.path[0].clone())
} else {
Err(Diagnostic::new(
DiagnosticKind::UnsupportedFeature,
field.span,
"nested let binding names are not supported",
))
}
}
fn primitive_type(name: &str) -> Option<PrimitiveType> {
match name {
"String" => Some(PrimitiveType::String),
"Int" => Some(PrimitiveType::Int),
"Float" => Some(PrimitiveType::Float),
"Bool" => Some(PrimitiveType::Bool),
_ => None,
}
}
fn literal_to_concrete(literal: Literal) -> ConcreteValue {
match literal {
Literal::String(value) => ConcreteValue::String(value),
Literal::Int(value) => ConcreteValue::Int(value),
Literal::Float(value) => ConcreteValue::Float(value),
Literal::Bool(value) => ConcreteValue::Bool(value),
}
}
fn literal_value_from_runtime(value: &RuntimeValue) -> Option<LiteralValue> {
match value {
RuntimeValue::Concrete(ConcreteValue::String(value)) => {
Some(LiteralValue::String(value.clone()))
}
RuntimeValue::Concrete(ConcreteValue::Int(value)) => Some(LiteralValue::Int(*value)),
RuntimeValue::Concrete(ConcreteValue::Float(value)) => Some(LiteralValue::Float(*value)),
RuntimeValue::Concrete(ConcreteValue::Bool(value)) => Some(LiteralValue::Bool(*value)),
_ => None,
}
}
fn value_matches_primitive(value: &RuntimeValue, primitive: PrimitiveType) -> bool {
matches!(
(value, primitive),
(
RuntimeValue::Concrete(ConcreteValue::String(_)),
PrimitiveType::String
) | (
RuntimeValue::Concrete(ConcreteValue::Int(_)),
PrimitiveType::Int
) | (
RuntimeValue::Concrete(ConcreteValue::Float(_)),
PrimitiveType::Float
) | (
RuntimeValue::Concrete(ConcreteValue::Bool(_)),
PrimitiveType::Bool
)
)
}
fn compare_value(value: &RuntimeValue, op: CompareOp, expected: &LiteralValue) -> bool {
match (value, expected) {
(RuntimeValue::Concrete(ConcreteValue::Int(actual)), LiteralValue::Int(expected)) => {
compare_f64(*actual as f64, op, *expected as f64)
}
(RuntimeValue::Concrete(ConcreteValue::Float(actual)), LiteralValue::Float(expected)) => {
compare_f64(*actual, op, *expected)
}
(RuntimeValue::Concrete(ConcreteValue::Int(actual)), LiteralValue::Float(expected)) => {
compare_f64(*actual as f64, op, *expected)
}
(RuntimeValue::Concrete(ConcreteValue::Float(actual)), LiteralValue::Int(expected)) => {
compare_f64(*actual, op, *expected as f64)
}
_ => false,
}
}
fn compare_f64(actual: f64, op: CompareOp, expected: f64) -> bool {
match op {
CompareOp::Gt => actual > expected,
CompareOp::Gte => actual >= expected,
CompareOp::Lt => actual < expected,
CompareOp::Lte => actual <= expected,
CompareOp::Eq => actual == expected,
}
}
fn concrete_scalar_eq(lhs: &ConcreteValue, rhs: &ConcreteValue) -> bool {
match (lhs, rhs) {
(ConcreteValue::String(lhs), ConcreteValue::String(rhs)) => lhs == rhs,
(ConcreteValue::Int(lhs), ConcreteValue::Int(rhs)) => lhs == rhs,
(ConcreteValue::Float(lhs), ConcreteValue::Float(rhs)) => lhs == rhs,
(ConcreteValue::Bool(lhs), ConcreteValue::Bool(rhs)) => lhs == rhs,
_ => false,
}
}
fn merge_default(
lhs: Option<ThunkId>,
rhs: Option<ThunkId>,
span: Span,
) -> Result<Option<ThunkId>> {
match (lhs, rhs) {
(None, None) => Ok(None),
(Some(value), None) | (None, Some(value)) => Ok(Some(value)),
(Some(lhs), Some(rhs)) if lhs == rhs => Ok(Some(lhs)),
(Some(_), Some(_)) => Err(Diagnostic::new(
DiagnosticKind::DefaultConflict,
span,
"conflicting defaults",
)),
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::parse_source;
fn eval_data(source: &str) -> Data {
let parsed = parse_source(source).unwrap();
let mut engine = Engine::from_parse(parsed.ast, parsed.root);
let value = engine.eval_root().unwrap();
engine.materialize(&value).unwrap()
}
#[test]
fn materializes_default() {
let data = eval_data("port = Int & >= 1 default 8080;");
assert!(matches!(data, Data::Object(_)));
}
#[test]
fn composes_schema_and_value() {
let data = eval_data(
r#"
let
MyConfig = { port = Int & > 443 default 8080; };
in
MyConfig & { port = 8000; }
"#,
);
let Data::Object(fields) = data else { panic!() };
assert_eq!(fields[0].name, "port");
assert_eq!(fields[0].value, Data::Int(8000));
}
#[test]
fn detects_constraint_violation() {
let parsed = parse_source("{ port = Int & > 443; } & { port = 80; }").unwrap();
let mut engine = Engine::from_parse(parsed.ast, parsed.root);
assert!(engine.eval_root().is_err());
}
}

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@ -4,14 +4,18 @@ extern crate alloc;
pub mod ast;
pub mod diagnostic;
pub mod eval;
pub mod lexer;
pub mod parser;
pub mod runtime;
pub mod span;
pub use ast::{Ast, BinaryOp, CompareOp, Expr, ExprId, Field, Literal, Param};
pub use diagnostic::{Diagnostic, DiagnosticKind, Result};
pub use eval::Engine;
pub use lexer::{Lexer, Token, TokenKind};
pub use parser::{ParseOutput, Parser, parse_source};
pub use runtime::{Data, RuntimeValue};
pub use span::Span;
pub fn version() -> &'static str {

View File

@ -0,0 +1,137 @@
use alloc::{string::String, vec::Vec};
use crate::{ExprId, ast::CompareOp};
#[derive(Debug, Clone, PartialEq)]
pub enum RuntimeValue {
Concrete(ConcreteValue),
Abstract(AbstractValue),
}
#[derive(Debug, Clone, PartialEq)]
pub enum ConcreteValue {
String(String),
Int(i64),
Float(f64),
Bool(bool),
Array(Vec<ThunkId>),
Object(ObjectValue),
Function(FunctionValue),
}
#[derive(Debug, Clone, PartialEq)]
pub struct ObjectValue {
pub fields: Vec<ObjectField>,
}
#[derive(Debug, Clone, PartialEq)]
pub struct ObjectField {
pub name: String,
pub value: ThunkId,
}
#[derive(Debug, Clone, PartialEq)]
pub struct FunctionValue {
pub params: Vec<FunctionParam>,
pub body: ExprId,
pub env: EnvId,
}
#[derive(Debug, Clone, PartialEq)]
pub struct FunctionParam {
pub name: String,
pub constraint: Option<ExprId>,
}
#[derive(Debug, Clone, PartialEq)]
pub struct AbstractValue {
pub constraints: Vec<Constraint>,
pub default: Option<ThunkId>,
}
#[derive(Debug, Clone, PartialEq)]
pub enum Constraint {
Type(PrimitiveType),
Compare(CompareOp, LiteralValue),
Regex(String),
BuiltinPredicate(String),
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum PrimitiveType {
String,
Int,
Float,
Bool,
}
#[derive(Debug, Clone, PartialEq)]
pub enum LiteralValue {
String(String),
Int(i64),
Float(f64),
Bool(bool),
}
#[derive(Debug, Clone, PartialEq)]
pub enum Data {
String(String),
Int(i64),
Float(f64),
Bool(bool),
Array(Vec<Data>),
Object(Vec<DataField>),
}
#[derive(Debug, Clone, PartialEq)]
pub struct DataField {
pub name: String,
pub value: Data,
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub struct ThunkId(pub u32);
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub struct EnvId(pub u32);
#[derive(Debug, Clone)]
pub struct Thunk {
pub kind: ThunkKind,
pub state: ThunkState,
}
#[derive(Debug, Clone)]
pub enum ThunkKind {
Expr {
expr: ExprId,
env: EnvId,
},
Constrained {
constraint: ExprId,
constraint_env: EnvId,
value: ExprId,
value_env: EnvId,
},
Value(RuntimeValue),
}
#[derive(Debug, Clone)]
pub enum ThunkState {
Unevaluated,
Evaluating,
Evaluated(RuntimeValue),
Error,
}
#[derive(Debug, Clone)]
pub struct Env {
pub parent: Option<EnvId>,
pub bindings: Vec<Binding>,
}
#[derive(Debug, Clone)]
pub struct Binding {
pub name: String,
pub value: ThunkId,
}

View File

@ -5,12 +5,11 @@
## 構文
```dcdl
import ./config.n
import "./config.n"
import "./config.dcdl"
```
パス表記の詳細は未確定である。
パスリテラルと文字列リテラルの両方を許可するか、どちらかに統一するかは今後決める
import specifier は文字列リテラルとする。
パスリテラル構文は採用しない
## モジュール
@ -25,19 +24,19 @@ import 先はモジュール単位で読み込まれる。
例:
```dcdl
# main.n
# main.dcdl
{
schema = {
hoge = String;
};
result = (import ./func.n)(schema);
result = (import "./func.dcdl")(schema);
}
```
```dcdl
# func.n
(input: (import ./main.n).schema) =>
# func.dcdl
(input: (import "./main.dcdl").schema) =>
{
# ...
}

View File

@ -9,7 +9,6 @@
- 演算子の優先順位。
- `rec` の扱い。
- コメント構文を `#` のみにするか。
- パス import と文字列 import の扱い分け。
## 型・制約