std.array_list: add a comment on every methods invalidating pointers.

While it is already mentioned on the `items` attributes of the structs, it is
interesting to comment in every method potentially invalidating pointers to items
that they may do so.
This commit is contained in:
remeh 2022-10-31 18:19:55 +01:00 committed by Veikka Tuominen
parent 3c0c0f899b
commit e7424d5d2a

View file

@ -116,6 +116,7 @@ pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
/// Insert `item` at index `n` by moving `list[n .. list.len]` to make room. /// Insert `item` at index `n` by moving `list[n .. list.len]` to make room.
/// This operation is O(N). /// This operation is O(N).
/// Invalidates pointers if additional memory is needed.
pub fn insert(self: *Self, n: usize, item: T) Allocator.Error!void { pub fn insert(self: *Self, n: usize, item: T) Allocator.Error!void {
try self.ensureUnusedCapacity(1); try self.ensureUnusedCapacity(1);
self.items.len += 1; self.items.len += 1;
@ -126,6 +127,7 @@ pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
/// Insert slice `items` at index `i` by moving `list[i .. list.len]` to make room. /// Insert slice `items` at index `i` by moving `list[i .. list.len]` to make room.
/// This operation is O(N). /// This operation is O(N).
/// Invalidates pointers if additional memory is needed.
pub fn insertSlice(self: *Self, i: usize, items: []const T) Allocator.Error!void { pub fn insertSlice(self: *Self, i: usize, items: []const T) Allocator.Error!void {
try self.ensureUnusedCapacity(items.len); try self.ensureUnusedCapacity(items.len);
self.items.len += items.len; self.items.len += items.len;
@ -163,6 +165,7 @@ pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
} }
/// Extend the list by 1 element. Allocates more memory as necessary. /// Extend the list by 1 element. Allocates more memory as necessary.
/// Invalidates pointers if additional memory is needed.
pub fn append(self: *Self, item: T) Allocator.Error!void { pub fn append(self: *Self, item: T) Allocator.Error!void {
const new_item_ptr = try self.addOne(); const new_item_ptr = try self.addOne();
new_item_ptr.* = item; new_item_ptr.* = item;
@ -205,6 +208,7 @@ pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
/// Append the slice of items to the list. Allocates more /// Append the slice of items to the list. Allocates more
/// memory as necessary. /// memory as necessary.
/// Invalidates pointers if additional memory is needed.
pub fn appendSlice(self: *Self, items: []const T) Allocator.Error!void { pub fn appendSlice(self: *Self, items: []const T) Allocator.Error!void {
try self.ensureUnusedCapacity(items.len); try self.ensureUnusedCapacity(items.len);
self.appendSliceAssumeCapacity(items); self.appendSliceAssumeCapacity(items);
@ -223,6 +227,7 @@ pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
/// Append an unaligned slice of items to the list. Allocates more /// Append an unaligned slice of items to the list. Allocates more
/// memory as necessary. Only call this function if calling /// memory as necessary. Only call this function if calling
/// `appendSlice` instead would be a compile error. /// `appendSlice` instead would be a compile error.
/// Invalidates pointers if additional memory is needed.
pub fn appendUnalignedSlice(self: *Self, items: []align(1) const T) Allocator.Error!void { pub fn appendUnalignedSlice(self: *Self, items: []align(1) const T) Allocator.Error!void {
try self.ensureUnusedCapacity(items.len); try self.ensureUnusedCapacity(items.len);
self.appendUnalignedSliceAssumeCapacity(items); self.appendUnalignedSliceAssumeCapacity(items);
@ -257,6 +262,7 @@ pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
/// Same as `append` except it returns the number of bytes written, which is always the same /// Same as `append` except it returns the number of bytes written, which is always the same
/// as `m.len`. The purpose of this function existing is to match `std.io.Writer` API. /// as `m.len`. The purpose of this function existing is to match `std.io.Writer` API.
/// Invalidates pointers if additional memory is needed.
fn appendWrite(self: *Self, m: []const u8) Allocator.Error!usize { fn appendWrite(self: *Self, m: []const u8) Allocator.Error!usize {
try self.appendSlice(m); try self.appendSlice(m);
return m.len; return m.len;
@ -264,6 +270,7 @@ pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
/// Append a value to the list `n` times. /// Append a value to the list `n` times.
/// Allocates more memory as necessary. /// Allocates more memory as necessary.
/// Invalidates pointers if additional memory is needed.
pub fn appendNTimes(self: *Self, value: T, n: usize) Allocator.Error!void { pub fn appendNTimes(self: *Self, value: T, n: usize) Allocator.Error!void {
const old_len = self.items.len; const old_len = self.items.len;
try self.resize(self.items.len + n); try self.resize(self.items.len + n);
@ -281,6 +288,7 @@ pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
/// Adjust the list's length to `new_len`. /// Adjust the list's length to `new_len`.
/// Does not initialize added items if any. /// Does not initialize added items if any.
/// Invalidates pointers if additional memory is needed.
pub fn resize(self: *Self, new_len: usize) Allocator.Error!void { pub fn resize(self: *Self, new_len: usize) Allocator.Error!void {
try self.ensureTotalCapacity(new_len); try self.ensureTotalCapacity(new_len);
self.items.len = new_len; self.items.len = new_len;
@ -527,6 +535,7 @@ pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) typ
/// Insert `item` at index `n`. Moves `list[n .. list.len]` /// Insert `item` at index `n`. Moves `list[n .. list.len]`
/// to higher indices to make room. /// to higher indices to make room.
/// This operation is O(N). /// This operation is O(N).
/// Invalidates pointers if additional memory is needed.
pub fn insert(self: *Self, allocator: Allocator, n: usize, item: T) Allocator.Error!void { pub fn insert(self: *Self, allocator: Allocator, n: usize, item: T) Allocator.Error!void {
try self.ensureUnusedCapacity(allocator, 1); try self.ensureUnusedCapacity(allocator, 1);
self.items.len += 1; self.items.len += 1;
@ -538,6 +547,7 @@ pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) typ
/// Insert slice `items` at index `i`. Moves `list[i .. list.len]` to /// Insert slice `items` at index `i`. Moves `list[i .. list.len]` to
/// higher indicices make room. /// higher indicices make room.
/// This operation is O(N). /// This operation is O(N).
/// Invalidates pointers if additional memory is needed.
pub fn insertSlice(self: *Self, allocator: Allocator, i: usize, items: []const T) Allocator.Error!void { pub fn insertSlice(self: *Self, allocator: Allocator, i: usize, items: []const T) Allocator.Error!void {
try self.ensureUnusedCapacity(allocator, items.len); try self.ensureUnusedCapacity(allocator, items.len);
self.items.len += items.len; self.items.len += items.len;
@ -557,6 +567,7 @@ pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) typ
} }
/// Extend the list by 1 element. Allocates more memory as necessary. /// Extend the list by 1 element. Allocates more memory as necessary.
/// Invalidates pointers if additional memory is needed.
pub fn append(self: *Self, allocator: Allocator, item: T) Allocator.Error!void { pub fn append(self: *Self, allocator: Allocator, item: T) Allocator.Error!void {
const new_item_ptr = try self.addOne(allocator); const new_item_ptr = try self.addOne(allocator);
new_item_ptr.* = item; new_item_ptr.* = item;
@ -598,6 +609,7 @@ pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) typ
/// Append the slice of items to the list. Allocates more /// Append the slice of items to the list. Allocates more
/// memory as necessary. /// memory as necessary.
/// Invalidates pointers if additional memory is needed.
pub fn appendSlice(self: *Self, allocator: Allocator, items: []const T) Allocator.Error!void { pub fn appendSlice(self: *Self, allocator: Allocator, items: []const T) Allocator.Error!void {
try self.ensureUnusedCapacity(allocator, items.len); try self.ensureUnusedCapacity(allocator, items.len);
self.appendSliceAssumeCapacity(items); self.appendSliceAssumeCapacity(items);
@ -616,6 +628,7 @@ pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) typ
/// Append the slice of items to the list. Allocates more /// Append the slice of items to the list. Allocates more
/// memory as necessary. Only call this function if a call to `appendSlice` instead would /// memory as necessary. Only call this function if a call to `appendSlice` instead would
/// be a compile error. /// be a compile error.
/// Invalidates pointers if additional memory is needed.
pub fn appendUnalignedSlice(self: *Self, allocator: Allocator, items: []align(1) const T) Allocator.Error!void { pub fn appendUnalignedSlice(self: *Self, allocator: Allocator, items: []align(1) const T) Allocator.Error!void {
try self.ensureUnusedCapacity(allocator, items.len); try self.ensureUnusedCapacity(allocator, items.len);
self.appendUnalignedSliceAssumeCapacity(items); self.appendUnalignedSliceAssumeCapacity(items);
@ -654,6 +667,7 @@ pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) typ
/// Same as `append` except it returns the number of bytes written, which is always the same /// Same as `append` except it returns the number of bytes written, which is always the same
/// as `m.len`. The purpose of this function existing is to match `std.io.Writer` API. /// as `m.len`. The purpose of this function existing is to match `std.io.Writer` API.
/// Invalidates pointers if additional memory is needed.
fn appendWrite(context: WriterContext, m: []const u8) Allocator.Error!usize { fn appendWrite(context: WriterContext, m: []const u8) Allocator.Error!usize {
try context.self.appendSlice(context.allocator, m); try context.self.appendSlice(context.allocator, m);
return m.len; return m.len;
@ -661,6 +675,7 @@ pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) typ
/// Append a value to the list `n` times. /// Append a value to the list `n` times.
/// Allocates more memory as necessary. /// Allocates more memory as necessary.
/// Invalidates pointers if additional memory is needed.
pub fn appendNTimes(self: *Self, allocator: Allocator, value: T, n: usize) Allocator.Error!void { pub fn appendNTimes(self: *Self, allocator: Allocator, value: T, n: usize) Allocator.Error!void {
const old_len = self.items.len; const old_len = self.items.len;
try self.resize(allocator, self.items.len + n); try self.resize(allocator, self.items.len + n);
@ -679,6 +694,7 @@ pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) typ
/// Adjust the list's length to `new_len`. /// Adjust the list's length to `new_len`.
/// Does not initialize added items, if any. /// Does not initialize added items, if any.
/// Invalidates pointers if additional memory is needed.
pub fn resize(self: *Self, allocator: Allocator, new_len: usize) Allocator.Error!void { pub fn resize(self: *Self, allocator: Allocator, new_len: usize) Allocator.Error!void {
try self.ensureTotalCapacity(allocator, new_len); try self.ensureTotalCapacity(allocator, new_len);
self.items.len = new_len; self.items.len = new_len;