Function computeConstantValue

test/fixtures/snapshot/typescript.js:84716–84834

(member)

            return undefined;
        }
        function computeConstantValue(member) {
            var enumKind = getEnumKind(getSymbolOfNode(member.parent));
            var isConstEnum = ts.isEnumConst(member.parent);
            var initializer = member.initializer;
            var value = enumKind === 1 /* EnumKind.Literal */ && !isLiteralEnumMember(member) ? undefined : evaluate(initializer);
            if (value !== undefined) {
                if (isConstEnum && typeof value === "number" && !isFinite(value)) {
                    error(initializer, isNaN(value) ?
                        ts.Diagnostics.const_enum_member_initializer_was_evaluated_to_disallowed_value_NaN :
                        ts.Diagnostics.const_enum_member_initializer_was_evaluated_to_a_non_finite_value);
                }
            }
            else if (enumKind === 1 /* EnumKind.Literal */) {
                error(initializer, ts.Diagnostics.Computed_values_are_not_permitted_in_an_enum_with_string_valued_members);
                return 0;
            }
            else if (isConstEnum) {
                error(initializer, ts.Diagnostics.const_enum_member_initializers_can_only_contain_literal_values_and_other_computed_enum_values);
            }
            else if (member.parent.flags & 16777216 /* NodeFlags.Ambient */) {
                error(initializer, ts.Diagnostics.In_ambient_enum_declarations_member_initializer_must_be_constant_expression);
            }
            else {
                // Only here do we need to check that the initializer is assignable to the enum type.
                var source = checkExpression(initializer);
                if (!isTypeAssignableToKind(source, 296 /* TypeFlags.NumberLike */)) {
                    error(initializer, ts.Diagnostics.Only_numeric_enums_can_have_computed_members_but_this_expression_has_type_0_If_you_do_not_need_exhaustiveness_checks_consider_using_an_object_literal_instead, typeToString(source));
                }
                else {
                    checkTypeAssignableTo(source, getDeclaredTypeOfSymbol(getSymbolOfNode(member.parent)), initializer, /*headMessage*/ undefined);
                }
            }
            return value;
            function evaluate(expr) {
                switch (expr.kind) {
                    case 219 /* SyntaxKind.PrefixUnaryExpression */:
                        var value_2 = evaluate(expr.operand);
                        if (typeof value_2 === "number") {
                            switch (expr.operator) {
                                case 39 /* SyntaxKind.PlusToken */: return value_2;
                                case 40 /* SyntaxKind.MinusToken */: return -value_2;
                                case 54 /* SyntaxKind.TildeToken */: return ~value_2;
                            }
                        }
                        break;
                    case 221 /* SyntaxKind.BinaryExpression */:
                        var left = evaluate(expr.left);
                        var right = evaluate(expr.right);
                        if (typeof left === "number" && typeof right === "number") {
                            switch (expr.operatorToken.kind) {
                                case 51 /* SyntaxKind.BarToken */: return left | right;
                                case 50 /* SyntaxKind.AmpersandToken */: return left & right;
                                case 48 /* SyntaxKind.GreaterThanGreaterThanToken */: return left >> right;
                                case 49 /* SyntaxKind.GreaterThanGreaterThanGreaterThanToken */: return left >>> right;
                                case 47 /* SyntaxKind.LessThanLessThanToken */: return left << right;
                                case 52 /* SyntaxKind.CaretToken */: return left ^ right;
                                case 41 /* SyntaxKind.AsteriskToken */: return left * right;
                                case 43 /* SyntaxKind.SlashToken */: return left / right;