tiny.choir.NamedAttributeList

1pub const NamedAttributeList = struct {2    const small_capacity = 4;34    len: usize = 0,5    owned_items: []NamedAttribute = &.{},6    small_items: [small_capacity]NamedAttribute = undefined,78    pub const Lookup = struct {9        found: bool,10        index: usize,11    };1213    pub fn items(self: *const NamedAttributeList) []const NamedAttribute {14        if (self.owned_items.len != 0) return self.owned_items[0..self.len];15        return self.small_items[0..self.len];16    }1718    pub fn capacity(self: *const NamedAttributeList) usize {19        if (self.owned_items.len != 0) return self.owned_items.len;20        return small_capacity;21    }2223    fn storage(self: *NamedAttributeList) []NamedAttribute {24        if (self.owned_items.len != 0) return self.owned_items;25        return self.small_items[0..];26    }2728    pub fn deinit(self: *NamedAttributeList, allocator: std.mem.Allocator) void {29        if (self.owned_items.len != 0) allocator.free(self.owned_items);30        self.len = 0;31        self.owned_items = &.{};32    }3334    pub fn clearRetainingCapacity(self: *NamedAttributeList) void {35        self.len = 0;36    }3738    pub fn ensureTotalCapacity(39        self: *NamedAttributeList,40        allocator: std.mem.Allocator,41        target_capacity: usize,42    ) std.mem.Allocator.Error!void {43        if (target_capacity <= self.capacity()) return;44        if (self.owned_items.len != 0) {45            self.owned_items = try allocator.realloc(self.owned_items, target_capacity);46            return;47        }48        const allocated_items = try allocator.alloc(NamedAttribute, target_capacity);49        @memcpy(allocated_items[0..self.len], self.small_items[0..self.len]);50        self.owned_items = allocated_items;51    }5253    pub fn get(self: *const NamedAttributeList, name: []const u8) ?Attribute {54        const result = self.findIndexOrInsertPos(name);55        if (!result.found) return null;56        return self.items()[result.index].value;57    }5859    pub fn getNamed(self: *const NamedAttributeList, name: []const u8) ?NamedAttribute {60        const result = self.findIndexOrInsertPos(name);61        if (!result.found) return null;62        return self.items()[result.index];63    }6465    pub fn set(66        self: *NamedAttributeList,67        allocator: std.mem.Allocator,68        attr_name: []const u8,69        value: Attribute,70    ) !?Attribute {71        const result = self.findIndexOrInsertPos(attr_name);72        if (result.found) {73            const storage_items = self.storage();74            const previous = storage_items[result.index].value;75            storage_items[result.index].value = value;76            return previous;77        }78        const required_capacity = std.math.add(usize, self.len, 1) catch79            return error.OutOfMemory;80        if (required_capacity > self.capacity()) {81            try self.ensureTotalCapacity(82                allocator,83                @max(required_capacity, self.capacity() *| 2),84            );85        }86        const storage_items = self.storage();87        std.mem.copyBackwards(NamedAttribute, storage_items[result.index + 1 .. self.len + 1], storage_items[result.index..self.len]);88        storage_items[result.index] = .{ .name = attr_name, .value = value };89        self.len += 1;90        return null;91    }9293    pub fn erase(self: *NamedAttributeList, attr_name: []const u8) ?Attribute {94        const result = self.findIndexOrInsertPos(attr_name);95        if (!result.found) return null;96        const storage_items = self.storage();97        const previous = storage_items[result.index].value;98        std.mem.copyForwards(NamedAttribute, storage_items[result.index .. self.len - 1], storage_items[result.index + 1 .. self.len]);99        self.len -= 1;100        return previous;101    }102103    pub fn findIndexOrInsertPos(self: *const NamedAttributeList, name: []const u8) Lookup {104        var left: usize = 0;105        const current_items = self.items();106        var right: usize = current_items.len;107        while (left < right) {108            const mid = left + (right - left) / 2;109            const cmp = std.mem.order(u8, current_items[mid].name, name);110            switch (cmp) {111                .eq => return .{ .found = true, .index = mid },112                .lt => left = mid + 1,113                .gt => right = mid,114            }115        }116        return .{ .found = false, .index = left };117    }118};

1pub const NamedAttributeList = ir.NamedAttributeList;