cairo_lang_semantic/items/
constant.rs

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use std::sync::Arc;

use cairo_lang_debug::DebugWithDb;
use cairo_lang_defs::ids::{
    ConstantId, GenericParamId, LanguageElementId, LookupItemId, ModuleItemId,
    NamedLanguageElementId, TraitConstantId,
};
use cairo_lang_diagnostics::{skip_diagnostic, DiagnosticAdded, Diagnostics, Maybe, ToMaybe};
use cairo_lang_proc_macros::{DebugWithDb, SemanticObject};
use cairo_lang_syntax::node::ast::ItemConstant;
use cairo_lang_syntax::node::ids::SyntaxStablePtrId;
use cairo_lang_syntax::node::{TypedStablePtr, TypedSyntaxNode};
use cairo_lang_utils::{
    define_short_id, extract_matches, try_extract_matches, Intern, LookupIntern,
};
use id_arena::Arena;
use itertools::Itertools;
use num_bigint::BigInt;
use num_traits::{Num, ToPrimitive, Zero};
use smol_str::SmolStr;

use super::functions::{GenericFunctionId, GenericFunctionWithBodyId};
use super::imp::ImplId;
use crate::corelib::{
    core_box_ty, core_felt252_ty, core_nonzero_ty, get_core_trait, get_core_ty_by_name,
    try_extract_nz_wrapped_type, validate_literal, CoreTraitContext, LiteralError,
};
use crate::db::SemanticGroup;
use crate::diagnostic::{SemanticDiagnosticKind, SemanticDiagnostics, SemanticDiagnosticsBuilder};
use crate::expr::compute::{
    compute_expr_semantic, ComputationContext, ContextFunction, Environment, ExprAndId,
};
use crate::expr::inference::conform::InferenceConform;
use crate::expr::inference::{ConstVar, InferenceId};
use crate::literals::try_extract_minus_literal;
use crate::resolve::{Resolver, ResolverData};
use crate::types::resolve_type;
use crate::{
    semantic_object_for_id, ConcreteTypeId, ConcreteVariant, Expr, ExprBlock, ExprConstant,
    ExprFunctionCall, ExprFunctionCallArg, ExprId, ExprMemberAccess, ExprStructCtor, FunctionId,
    GenericParam, SemanticDiagnostic, TypeId, TypeLongId,
};

#[derive(Clone, Debug, PartialEq, Eq, DebugWithDb)]
#[debug_db(dyn SemanticGroup + 'static)]
pub struct Constant {
    /// The actual id of the const expression value.
    pub value: ExprId,
    /// The arena of all the expressions for the const calculation.
    pub exprs: Arc<Arena<Expr>>,
}

impl Constant {
    pub fn ty(&self) -> TypeId {
        self.exprs[self.value].ty()
    }
}

/// Information about a constant definition.
///
/// Helper struct for the data returned by [SemanticGroup::priv_constant_semantic_data].
#[derive(Clone, Debug, PartialEq, Eq, DebugWithDb)]
#[debug_db(dyn SemanticGroup + 'static)]
pub struct ConstantData {
    pub diagnostics: Diagnostics<SemanticDiagnostic>,
    pub constant: Maybe<Constant>,
    pub const_value: ConstValue,
    pub resolver_data: Arc<ResolverData>,
}

define_short_id!(
    ConstValueId,
    ConstValue,
    SemanticGroup,
    lookup_intern_const_value,
    intern_const_value
);
semantic_object_for_id!(ConstValueId, lookup_intern_const_value, intern_const_value, ConstValue);
impl ConstValueId {
    pub fn format(&self, db: &dyn SemanticGroup) -> String {
        format!("{:?}", self.lookup_intern(db).debug(db.elongate()))
    }

    /// Returns true if the const does not depend on any generics.
    pub fn is_fully_concrete(&self, db: &dyn SemanticGroup) -> bool {
        self.lookup_intern(db).is_fully_concrete(db)
    }

    /// Returns true if the const does not contain any inference variables.
    pub fn is_var_free(&self, db: &dyn SemanticGroup) -> bool {
        self.lookup_intern(db).is_var_free(db)
    }

    /// Returns the type of the const.
    pub fn ty(&self, db: &dyn SemanticGroup) -> Maybe<TypeId> {
        self.lookup_intern(db).ty(db)
    }
}

/// A constant value.
#[derive(Clone, Debug, Hash, PartialEq, Eq, SemanticObject)]
pub enum ConstValue {
    Int(#[dont_rewrite] BigInt, TypeId),
    Struct(Vec<ConstValue>, TypeId),
    Enum(ConcreteVariant, Box<ConstValue>),
    NonZero(Box<ConstValue>),
    Boxed(Box<ConstValue>),
    Generic(#[dont_rewrite] GenericParamId),
    ImplConstant(ImplConstantId),
    TraitConstant(TraitConstantId),
    Var(ConstVar, TypeId),
    /// A missing value, used in cases where the value is not known due to diagnostics.
    Missing(#[dont_rewrite] DiagnosticAdded),
}
impl ConstValue {
    /// Returns true if the const does not depend on any generics.
    pub fn is_fully_concrete(&self, db: &dyn SemanticGroup) -> bool {
        self.ty(db).unwrap().is_fully_concrete(db)
            && match self {
                ConstValue::Int(_, _) => true,
                ConstValue::Struct(members, _) => {
                    members.iter().all(|member: &ConstValue| member.is_fully_concrete(db))
                }
                ConstValue::Enum(_, value)
                | ConstValue::NonZero(value)
                | ConstValue::Boxed(value) => value.is_fully_concrete(db),
                ConstValue::Generic(_)
                | ConstValue::Var(_, _)
                | ConstValue::Missing(_)
                | ConstValue::ImplConstant(_)
                | ConstValue::TraitConstant(_) => false,
            }
    }

    /// Returns true if the const does not contain any inference variables.
    pub fn is_var_free(&self, db: &dyn SemanticGroup) -> bool {
        self.ty(db).unwrap().is_var_free(db)
            && match self {
                ConstValue::Int(_, _)
                | ConstValue::Generic(_)
                | ConstValue::Missing(_)
                | ConstValue::TraitConstant(_) => true,
                ConstValue::Struct(members, _) => {
                    members.iter().all(|member| member.is_var_free(db))
                }
                ConstValue::Enum(_, value)
                | ConstValue::NonZero(value)
                | ConstValue::Boxed(value) => value.is_var_free(db),
                ConstValue::Var(_, _) => false,
                ConstValue::ImplConstant(impl_constant) => impl_constant.impl_id().is_var_free(db),
            }
    }

    /// Returns the type of the const.
    pub fn ty(&self, db: &dyn SemanticGroup) -> Maybe<TypeId> {
        Ok(match self {
            ConstValue::Int(_, ty) => *ty,
            ConstValue::Struct(_, ty) => *ty,
            ConstValue::Enum(variant, _) => {
                TypeLongId::Concrete(ConcreteTypeId::Enum(variant.concrete_enum_id)).intern(db)
            }
            ConstValue::NonZero(value) => core_nonzero_ty(db, value.ty(db)?),
            ConstValue::Boxed(value) => core_box_ty(db, value.ty(db)?),
            ConstValue::Generic(param) => {
                extract_matches!(db.generic_param_semantic(*param)?, GenericParam::Const).ty
            }
            ConstValue::Var(_, ty) => *ty,
            ConstValue::Missing(_) => TypeId::missing(db, skip_diagnostic()),
            ConstValue::ImplConstant(impl_constant_id) => {
                db.impl_constant_concrete_implized_type(*impl_constant_id)?
            }
            ConstValue::TraitConstant(trait_constant) => db.trait_constant_type(*trait_constant)?,
        })
    }

    /// Returns the value of an int const as a BigInt.
    pub fn into_int(self) -> Option<BigInt> {
        match self {
            ConstValue::Int(value, _) => Some(value.clone()),
            _ => None,
        }
    }
}

/// An impl item of kind const.
#[derive(Copy, Clone, Debug, Hash, PartialEq, Eq, SemanticObject)]
pub struct ImplConstantId {
    /// The impl the item const is in.
    impl_id: ImplId,
    /// The trait const this impl const "implements".
    trait_constant_id: TraitConstantId,
}

impl ImplConstantId {
    /// Creates a new impl constant id. For an impl constant of a concrete impl, asserts that the
    /// trait constant belongs to the same trait that the impl implements (panics if not).
    pub fn new(
        impl_id: ImplId,
        trait_constant_id: TraitConstantId,
        db: &dyn SemanticGroup,
    ) -> Self {
        if let crate::items::imp::ImplLongId::Concrete(concrete_impl) = impl_id.lookup_intern(db) {
            let impl_def_id = concrete_impl.impl_def_id(db);
            assert_eq!(Ok(trait_constant_id.trait_id(db.upcast())), db.impl_def_trait(impl_def_id));
        }

        ImplConstantId { impl_id, trait_constant_id }
    }
    pub fn impl_id(&self) -> ImplId {
        self.impl_id
    }
    pub fn trait_constant_id(&self) -> TraitConstantId {
        self.trait_constant_id
    }

    pub fn format(&self, db: &dyn SemanticGroup) -> SmolStr {
        format!("{}::{}", self.impl_id.name(db.upcast()), self.trait_constant_id.name(db.upcast()))
            .into()
    }
}
impl DebugWithDb<dyn SemanticGroup> for ImplConstantId {
    fn fmt(
        &self,
        f: &mut std::fmt::Formatter<'_>,
        db: &(dyn SemanticGroup + 'static),
    ) -> std::fmt::Result {
        write!(f, "{}", self.format(db))
    }
}

/// Query implementation of [SemanticGroup::priv_constant_semantic_data].
pub fn priv_constant_semantic_data(
    db: &dyn SemanticGroup,
    const_id: ConstantId,
    in_cycle: bool,
) -> Maybe<ConstantData> {
    let lookup_item_id = LookupItemId::ModuleItem(ModuleItemId::Constant(const_id));
    if in_cycle {
        constant_semantic_data_cycle_helper(
            db,
            &db.module_constant_by_id(const_id)?.to_maybe()?,
            lookup_item_id,
            None,
            &const_id,
        )
    } else {
        constant_semantic_data_helper(
            db,
            &db.module_constant_by_id(const_id)?.to_maybe()?,
            lookup_item_id,
            None,
            &const_id,
        )
    }
}

/// Cycle handling for [SemanticGroup::priv_constant_semantic_data].
pub fn priv_constant_semantic_data_cycle(
    db: &dyn SemanticGroup,
    _cycle: &salsa::Cycle,
    const_id: &ConstantId,
    _in_cycle: &bool,
) -> Maybe<ConstantData> {
    priv_constant_semantic_data(db, *const_id, true)
}

/// Returns constant semantic data for the given ItemConstant.
pub fn constant_semantic_data_helper(
    db: &dyn SemanticGroup,
    constant_ast: &ItemConstant,
    lookup_item_id: LookupItemId,
    parent_resolver_data: Option<Arc<ResolverData>>,
    element_id: &impl LanguageElementId,
) -> Maybe<ConstantData> {
    let mut diagnostics: SemanticDiagnostics = SemanticDiagnostics::default();
    // TODO(spapini): when code changes in a file, all the AST items change (as they contain a path
    // to the green root that changes. Once ASTs are rooted on items, use a selector that picks only
    // the item instead of all the module data.
    let syntax_db = db.upcast();

    let inference_id = InferenceId::LookupItemDeclaration(lookup_item_id);

    let mut resolver = match parent_resolver_data {
        Some(parent_resolver_data) => {
            Resolver::with_data(db, parent_resolver_data.clone_with_inference_id(db, inference_id))
        }
        None => Resolver::new(db, element_id.module_file_id(db.upcast()), inference_id),
    };
    resolver.set_feature_config(element_id, constant_ast, &mut diagnostics);

    let constant_type = resolve_type(
        db,
        &mut diagnostics,
        &mut resolver,
        &constant_ast.type_clause(syntax_db).ty(syntax_db),
    );

    let environment = Environment::empty();
    let mut ctx = ComputationContext::new(
        db,
        &mut diagnostics,
        resolver,
        None,
        environment,
        ContextFunction::Global,
    );

    let value = compute_expr_semantic(&mut ctx, &constant_ast.value(syntax_db));
    let const_value = resolve_const_expr_and_evaluate(
        db,
        &mut ctx,
        &value,
        constant_ast.stable_ptr().untyped(),
        constant_type,
    );

    // Check fully resolved.
    ctx.resolver.inference().finalize(ctx.diagnostics, constant_ast.stable_ptr().untyped());
    ctx.apply_inference_rewriter_to_exprs();

    let resolver_data = Arc::new(ctx.resolver.data);
    let constant = Constant { value: value.id, exprs: Arc::new(ctx.arenas.exprs) };
    Ok(ConstantData {
        diagnostics: diagnostics.build(),
        const_value,
        constant: Ok(constant),
        resolver_data,
    })
}

/// Helper for cycle handling of constants.
pub fn constant_semantic_data_cycle_helper(
    db: &dyn SemanticGroup,
    constant_ast: &ItemConstant,
    lookup_item_id: LookupItemId,
    parent_resolver_data: Option<Arc<ResolverData>>,
    element_id: &impl LanguageElementId,
) -> Maybe<ConstantData> {
    let mut diagnostics: SemanticDiagnostics = SemanticDiagnostics::default();

    let inference_id = InferenceId::LookupItemDeclaration(lookup_item_id);

    let resolver = match parent_resolver_data {
        Some(parent_resolver_data) => {
            Resolver::with_data(db, parent_resolver_data.clone_with_inference_id(db, inference_id))
        }
        None => Resolver::new(db, element_id.module_file_id(db.upcast()), inference_id),
    };

    let resolver_data = Arc::new(resolver.data);

    let diagnostic_added = diagnostics.report(constant_ast, SemanticDiagnosticKind::ConstCycle);
    Ok(ConstantData {
        constant: Err(diagnostic_added),
        const_value: ConstValue::Missing(diagnostic_added),
        diagnostics: diagnostics.build(),
        resolver_data,
    })
}

/// Resolves the given const expression and evaluates its value.
pub fn resolve_const_expr_and_evaluate(
    db: &dyn SemanticGroup,
    ctx: &mut ComputationContext<'_>,
    value: &ExprAndId,
    const_stable_ptr: SyntaxStablePtrId,
    target_type: TypeId,
) -> ConstValue {
    let inference = &mut ctx.resolver.inference();
    if let Err(err_set) = inference.conform_ty(value.ty(), target_type) {
        inference.report_on_pending_error(err_set, ctx.diagnostics, const_stable_ptr);
    }

    if let Err(err_set) = inference.solve() {
        inference.report_on_pending_error(err_set, ctx.diagnostics, const_stable_ptr);
    }

    ctx.apply_inference_rewriter_to_exprs();

    match &value.expr {
        Expr::Constant(ExprConstant { const_value_id, .. }) => const_value_id.lookup_intern(db),
        // Check that the expression is a valid constant.
        _ => evaluate_constant_expr(db, &ctx.arenas.exprs, value.id, ctx.diagnostics),
    }
}

/// creates a [ConstValue] from a [BigInt] value.
pub fn value_as_const_value(
    db: &dyn SemanticGroup,
    ty: TypeId,
    value: &BigInt,
) -> Result<ConstValue, LiteralError> {
    validate_literal(db.upcast(), ty, value.clone())?;
    let get_basic_const_value = |ty| {
        let u256_ty = get_core_ty_by_name(db.upcast(), "u256".into(), vec![]);

        if ty != u256_ty {
            ConstValue::Int(value.clone(), ty)
        } else {
            let u128_ty = get_core_ty_by_name(db.upcast(), "u128".into(), vec![]);
            let mask128 = BigInt::from(u128::MAX);
            let low = value & mask128;
            let high = value >> 128;
            ConstValue::Struct(
                vec![(ConstValue::Int(low, u128_ty)), (ConstValue::Int(high, u128_ty))],
                ty,
            )
        }
    };

    if let Some(inner) = try_extract_nz_wrapped_type(db.upcast(), ty) {
        Ok(ConstValue::NonZero(Box::new(get_basic_const_value(inner))))
    } else {
        Ok(get_basic_const_value(ty))
    }
}

/// evaluate the given const expression value.
pub fn evaluate_constant_expr(
    db: &dyn SemanticGroup,
    exprs: &Arena<Expr>,
    expr_id: ExprId,
    diagnostics: &mut SemanticDiagnostics,
) -> ConstValue {
    let expr = &exprs[expr_id];

    match expr {
        Expr::Constant(expr) => expr.const_value_id.lookup_intern(db),
        Expr::Block(ExprBlock { statements, tail: Some(inner), .. }) if statements.is_empty() => {
            evaluate_constant_expr(db, exprs, *inner, diagnostics)
        }
        Expr::FunctionCall(expr) => evaluate_const_function_call(db, exprs, expr, diagnostics)
            .map(|value| {
                value_as_const_value(db, expr.ty, &value)
                    .map_err(|err| {
                        diagnostics.report(
                            expr.stable_ptr.untyped(),
                            SemanticDiagnosticKind::LiteralError(err),
                        )
                    })
                    .unwrap_or_else(ConstValue::Missing)
            })
            .unwrap_or_else(ConstValue::Missing),
        Expr::Literal(expr) => value_as_const_value(db, expr.ty, &expr.value)
            .map_err(|err| {
                diagnostics
                    .report(expr.stable_ptr.untyped(), SemanticDiagnosticKind::LiteralError(err))
            })
            .unwrap_or_else(ConstValue::Missing),
        Expr::Tuple(expr) => ConstValue::Struct(
            expr.items
                .iter()
                .map(|expr_id| evaluate_constant_expr(db, exprs, *expr_id, diagnostics))
                .collect(),
            expr.ty,
        ),
        Expr::StructCtor(ExprStructCtor {
            members,
            base_struct: None,
            ty,
            concrete_struct_id,
            ..
        }) => {
            let member_order = match db.concrete_struct_members(*concrete_struct_id) {
                Ok(member_order) => member_order,
                Err(diag_add) => return ConstValue::Missing(diag_add),
            };
            ConstValue::Struct(
                member_order
                    .values()
                    .map(|m| {
                        members
                            .iter()
                            .find(|(member_id, _)| m.id == *member_id)
                            .map(|(_, expr_id)| {
                                evaluate_constant_expr(db, exprs, *expr_id, diagnostics)
                            })
                            .unwrap_or_else(|| ConstValue::Missing(skip_diagnostic()))
                    })
                    .collect(),
                *ty,
            )
        }
        Expr::EnumVariantCtor(expr) => ConstValue::Enum(
            expr.variant.clone(),
            Box::new(evaluate_constant_expr(db, exprs, expr.value_expr, diagnostics)),
        ),
        Expr::MemberAccess(expr) => extract_const_member_access(db, exprs, expr, diagnostics)
            .unwrap_or_else(ConstValue::Missing),
        Expr::FixedSizeArray(expr) => ConstValue::Struct(
            match &expr.items {
                crate::FixedSizeArrayItems::Items(items) => items
                    .iter()
                    .map(|expr_id| evaluate_constant_expr(db, exprs, *expr_id, diagnostics))
                    .collect(),
                crate::FixedSizeArrayItems::ValueAndSize(value, count) => {
                    let value = evaluate_constant_expr(db, exprs, *value, diagnostics);
                    let count = count.lookup_intern(db);
                    if let Some(count) = count.into_int() {
                        (0..count.to_usize().unwrap()).map(|_| value.clone()).collect()
                    } else {
                        diagnostics.report(
                            expr.stable_ptr.untyped(),
                            SemanticDiagnosticKind::UnsupportedConstant,
                        );
                        vec![]
                    }
                }
            },
            expr.ty,
        ),
        _ if diagnostics.error_count == 0 => ConstValue::Missing(
            diagnostics
                .report(expr.stable_ptr().untyped(), SemanticDiagnosticKind::UnsupportedConstant),
        ),
        _ => ConstValue::Missing(skip_diagnostic()),
    }
}

/// Returns true if the given function is allowed to be called in constant context.
fn is_function_const(db: &dyn SemanticGroup, function_id: FunctionId) -> bool {
    let concrete_function = function_id.get_concrete(db);
    let Ok(Some(body)) = concrete_function.body(db) else { return false };
    let GenericFunctionWithBodyId::Impl(imp) = body.generic_function(db) else { return false };
    let impl_def = imp.concrete_impl_id.impl_def_id(db);
    if impl_def.parent_module(db.upcast()).owning_crate(db.upcast()) != db.core_crate() {
        return false;
    }
    let Ok(trait_id) = db.impl_def_trait(impl_def) else {
        return false;
    };
    let expected_trait_name = match imp.function_body.name(db.upcast()).as_str() {
        "neg" => "Neg",
        "add" => "Add",
        "sub" => "Sub",
        "mul" => "Mul",
        "div" => "Div",
        "rem" => "Rem",
        "bitand" => "BitAnd",
        "bitor" => "BitOr",
        "bitxor" => "BitXor",
        _ => return false,
    };
    trait_id == get_core_trait(db, CoreTraitContext::TopLevel, expected_trait_name.into())
}

/// Attempts to evaluate constants from a function call.
fn evaluate_const_function_call(
    db: &dyn SemanticGroup,
    exprs: &Arena<Expr>,
    expr: &ExprFunctionCall,
    diagnostics: &mut SemanticDiagnostics,
) -> Maybe<BigInt> {
    if let Some(value) = try_extract_minus_literal(db.upcast(), exprs, expr) {
        return Ok(value);
    }
    let args = expr
        .args
        .iter()
        .filter_map(|arg| try_extract_matches!(arg, ExprFunctionCallArg::Value))
        .map(|arg| {
            match evaluate_constant_expr(db, exprs, *arg, diagnostics) {
                ConstValue::Int(v, _ty) => Ok(v),
                // Handling u256 constants to enable const evaluation of them.
                ConstValue::Struct(v, _) => {
                    if let [ConstValue::Int(low, _), ConstValue::Int(high, _)] = &v[..] {
                        Ok(low + (high << 128))
                    } else {
                        Err(diagnostics.report(
                            exprs[*arg].stable_ptr().untyped(),
                            SemanticDiagnosticKind::UnsupportedConstant,
                        ))
                    }
                }
                ConstValue::Missing(err) => Err(err),
                _ => Err(diagnostics.report(
                    exprs[*arg].stable_ptr().untyped(),
                    SemanticDiagnosticKind::UnsupportedConstant,
                )),
            }
        })
        .collect_vec()
        .into_iter()
        .collect::<Result<Vec<_>, _>>()?;

    if !is_function_const(db, expr.function) {
        return Err(diagnostics
            .report(expr.stable_ptr.untyped(), SemanticDiagnosticKind::UnsupportedConstant));
    }

    let imp = extract_matches!(
        expr.function.get_concrete(db.upcast()).generic_function,
        GenericFunctionId::Impl
    );
    let is_felt252_ty = expr.ty == core_felt252_ty(db.upcast());
    let mut value = match imp.function.name(db.upcast()).as_str() {
        "neg" => -&args[0],
        "add" => &args[0] + &args[1],
        "sub" => &args[0] - &args[1],
        "mul" => &args[0] * &args[1],
        "div" | "rem" if args[1].is_zero() => {
            return Err(diagnostics
                .report(expr.stable_ptr.untyped(), SemanticDiagnosticKind::DivisionByZero));
        }
        "div" if !is_felt252_ty => &args[0] / &args[1],
        "rem" if !is_felt252_ty => &args[0] % &args[1],
        "bitand" if !is_felt252_ty => &args[0] & &args[1],
        "bitor" if !is_felt252_ty => &args[0] | &args[1],
        "bitxor" if !is_felt252_ty => &args[0] ^ &args[1],
        _ => unreachable!("Unexpected function call in constant lowering: {:?}", expr),
    };
    if is_felt252_ty {
        // Specifically handling felt252s since their evaluation is more complex.
        value %= BigInt::from_str_radix(
            "800000000000011000000000000000000000000000000000000000000000001",
            16,
        )
        .unwrap();
    }
    Ok(value)
}

/// Extract const member access from a const value.
fn extract_const_member_access(
    db: &dyn SemanticGroup,
    exprs: &Arena<Expr>,
    expr: &ExprMemberAccess,
    diagnostics: &mut SemanticDiagnostics,
) -> Maybe<ConstValue> {
    let full_struct = evaluate_constant_expr(db, exprs, expr.expr, diagnostics);
    let ConstValue::Struct(mut values, _) = full_struct else {
        return Err(diagnostics.report(
            exprs[expr.expr].stable_ptr().untyped(),
            SemanticDiagnosticKind::UnsupportedConstant,
        ));
    };
    let members = db.concrete_struct_members(expr.concrete_struct_id)?;
    let Some(member_idx) = members.iter().position(|(_, member)| member.id == expr.member) else {
        return Err(diagnostics.report(
            exprs[expr.expr].stable_ptr().untyped(),
            SemanticDiagnosticKind::UnsupportedConstant,
        ));
    };
    Ok(values.swap_remove(member_idx))
}

/// Query implementation of [SemanticGroup::constant_semantic_diagnostics].
pub fn constant_semantic_diagnostics(
    db: &dyn SemanticGroup,
    const_id: ConstantId,
) -> Diagnostics<SemanticDiagnostic> {
    db.priv_constant_semantic_data(const_id, false).map(|data| data.diagnostics).unwrap_or_default()
}

/// Query implementation of [SemanticGroup::constant_semantic_data].
pub fn constant_semantic_data(db: &dyn SemanticGroup, const_id: ConstantId) -> Maybe<Constant> {
    db.priv_constant_semantic_data(const_id, false)?.constant
}

/// Cycle handling for [SemanticGroup::constant_semantic_data].
pub fn constant_semantic_data_cycle(
    db: &dyn SemanticGroup,
    _cycle: &salsa::Cycle,
    const_id: &ConstantId,
) -> Maybe<Constant> {
    // Forwarding cycle handling to `priv_constant_semantic_data` handler.
    db.priv_constant_semantic_data(*const_id, true)?.constant
}

/// Query implementation of [crate::db::SemanticGroup::constant_resolver_data].
pub fn constant_resolver_data(
    db: &dyn SemanticGroup,
    const_id: ConstantId,
) -> Maybe<Arc<ResolverData>> {
    Ok(db.priv_constant_semantic_data(const_id, false)?.resolver_data)
}

/// Cycle handling for [crate::db::SemanticGroup::constant_resolver_data].
pub fn constant_resolver_data_cycle(
    db: &dyn SemanticGroup,
    _cycle: &salsa::Cycle,
    const_id: &ConstantId,
) -> Maybe<Arc<ResolverData>> {
    Ok(db.priv_constant_semantic_data(*const_id, true)?.resolver_data)
}

/// Query implementation of [crate::db::SemanticGroup::constant_const_value].
pub fn constant_const_value(db: &dyn SemanticGroup, const_id: ConstantId) -> Maybe<ConstValue> {
    Ok(db.priv_constant_semantic_data(const_id, false)?.const_value)
}

/// Cycle handling for [crate::db::SemanticGroup::constant_const_value].
pub fn constant_const_value_cycle(
    db: &dyn SemanticGroup,
    _cycle: &salsa::Cycle,
    const_id: &ConstantId,
) -> Maybe<ConstValue> {
    // Forwarding cycle handling to `priv_constant_semantic_data` handler.
    Ok(db.priv_constant_semantic_data(*const_id, true)?.const_value)
}

/// Query implementation of [crate::db::SemanticGroup::constant_const_type].
pub fn constant_const_type(db: &dyn SemanticGroup, const_id: ConstantId) -> Maybe<TypeId> {
    db.priv_constant_semantic_data(const_id, false)?.const_value.ty(db)
}

/// Cycle handling for [crate::db::SemanticGroup::constant_const_type].
pub fn constant_const_type_cycle(
    db: &dyn SemanticGroup,
    _cycle: &salsa::Cycle,
    const_id: &ConstantId,
) -> Maybe<TypeId> {
    // Forwarding cycle handling to `priv_constant_semantic_data` handler.
    db.priv_constant_semantic_data(*const_id, true)?.const_value.ty(db)
}