basic language features do not belong in std.meta

This commit is contained in:
Andrew Kelley 2022-03-13 22:21:16 -07:00
parent eeaaefb925
commit d42d31f72f
3 changed files with 38 additions and 32 deletions

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@ -2515,13 +2515,14 @@ test "null terminated array" {
{#header_open|Vectors#} {#header_open|Vectors#}
<p> <p>
A vector is a group of booleans, {#link|Integers#}, {#link|Floats#}, or {#link|Pointers#} which are operated on A vector is a group of booleans, {#link|Integers#}, {#link|Floats#}, or
in parallel using SIMD instructions. Vector types are created with the builtin function {#link|@Type#}, {#link|Pointers#} which are operated on in parallel, using SIMD instructions if possible.
or using the shorthand function {#syntax#}std.meta.Vector{#endsyntax#}. Vector types are created with the builtin function {#link|@Vector#}.
</p> </p>
<p> <p>
Vectors support the same builtin operators as their underlying base types. These operations are performed Vectors support the same builtin operators as their underlying base types.
element-wise, and return a vector of the same length as the input vectors. This includes: These operations are performed element-wise, and return a vector of the same length
as the input vectors. This includes:
</p> </p>
<ul> <ul>
<li>Arithmetic ({#syntax#}+{#endsyntax#}, {#syntax#}-{#endsyntax#}, {#syntax#}/{#endsyntax#}, {#syntax#}*{#endsyntax#}, <li>Arithmetic ({#syntax#}+{#endsyntax#}, {#syntax#}-{#endsyntax#}, {#syntax#}/{#endsyntax#}, {#syntax#}*{#endsyntax#},
@ -2532,10 +2533,11 @@ test "null terminated array" {
<li>Comparison operators ({#syntax#}<{#endsyntax#}, {#syntax#}>{#endsyntax#}, {#syntax#}=={#endsyntax#}, etc.)</li> <li>Comparison operators ({#syntax#}<{#endsyntax#}, {#syntax#}>{#endsyntax#}, {#syntax#}=={#endsyntax#}, etc.)</li>
</ul> </ul>
<p> <p>
It is prohibited to use a math operator on a mixture of scalars (individual numbers) and vectors. It is prohibited to use a math operator on a mixture of scalars (individual numbers)
Zig provides the {#link|@splat#} builtin to easily convert from scalars to vectors, and it supports {#link|@reduce#} and vectors. Zig provides the {#link|@splat#} builtin to easily convert from scalars
and array indexing syntax to convert from vectors to scalars. Vectors also support assignment to and from to vectors, and it supports {#link|@reduce#} and array indexing syntax to convert
fixed-length arrays with comptime known length. from vectors to scalars. Vectors also support assignment to and from fixed-length
arrays with comptime known length.
</p> </p>
<p> <p>
For rearranging elements within and between vectors, Zig provides the {#link|@shuffle#} and {#link|@select#} functions. For rearranging elements within and between vectors, Zig provides the {#link|@shuffle#} and {#link|@select#} functions.
@ -2550,16 +2552,14 @@ test "null terminated array" {
</p> </p>
{#code_begin|test|vector_example#} {#code_begin|test|vector_example#}
const std = @import("std"); const std = @import("std");
const Vector = std.meta.Vector;
const expectEqual = std.testing.expectEqual; const expectEqual = std.testing.expectEqual;
test "Basic vector usage" { test "Basic vector usage" {
// Vectors have a compile-time known length and base type, // Vectors have a compile-time known length and base type.
// and can be assigned to using array literal syntax const a = @Vector(4, i32){ 1, 2, 3, 4 };
const a: Vector(4, i32) = [_]i32{ 1, 2, 3, 4 }; const b = @Vector(4, i32){ 5, 6, 7, 8 };
const b: Vector(4, i32) = [_]i32{ 5, 6, 7, 8 };
// Math operations take place element-wise // Math operations take place element-wise.
const c = a + b; const c = a + b;
// Individual vector elements can be accessed using array indexing syntax. // Individual vector elements can be accessed using array indexing syntax.
@ -2572,19 +2572,19 @@ test "Basic vector usage" {
test "Conversion between vectors, arrays, and slices" { test "Conversion between vectors, arrays, and slices" {
// Vectors and fixed-length arrays can be automatically assigned back and forth // Vectors and fixed-length arrays can be automatically assigned back and forth
var arr1: [4]f32 = [_]f32{ 1.1, 3.2, 4.5, 5.6 }; var arr1: [4]f32 = [_]f32{ 1.1, 3.2, 4.5, 5.6 };
var vec: Vector(4, f32) = arr1; var vec: @Vector(4, f32) = arr1;
var arr2: [4]f32 = vec; var arr2: [4]f32 = vec;
try expectEqual(arr1, arr2); try expectEqual(arr1, arr2);
// You can also assign from a slice with comptime-known length to a vector using .* // You can also assign from a slice with comptime-known length to a vector using .*
const vec2: Vector(2, f32) = arr1[1..3].*; const vec2: @Vector(2, f32) = arr1[1..3].*;
var slice: []const f32 = &arr1; var slice: []const f32 = &arr1;
var offset: u32 = 1; var offset: u32 = 1;
// To extract a comptime-known length from a runtime-known offset, // To extract a comptime-known length from a runtime-known offset,
// first extract a new slice from the starting offset, then an array of // first extract a new slice from the starting offset, then an array of
// comptime known length // comptime known length
const vec3: Vector(2, f32) = slice[offset..][0..2].*; const vec3: @Vector(2, f32) = slice[offset..][0..2].*;
try expectEqual(slice[offset], vec2[0]); try expectEqual(slice[offset], vec2[0]);
try expectEqual(slice[offset + 1], vec2[1]); try expectEqual(slice[offset + 1], vec2[1]);
try expectEqual(vec2, vec3); try expectEqual(vec2, vec3);
@ -9084,7 +9084,7 @@ pub const PrefetchOptions = struct {
{#header_close#} {#header_close#}
{#header_open|@select#} {#header_open|@select#}
<pre>{#syntax#}@select(comptime T: type, pred: std.meta.Vector(len, bool), a: std.meta.Vector(len, T), b: std.meta.Vector(len, T)) std.meta.Vector(len, T){#endsyntax#}</pre> <pre>{#syntax#}@select(comptime T: type, pred: @Vector(len, bool), a: @Vector(len, T), b: @Vector(len, T)) @Vector(len, T){#endsyntax#}</pre>
<p> <p>
Selects values element-wise from {#syntax#}a{#endsyntax#} or {#syntax#}b{#endsyntax#} based on {#syntax#}pred{#endsyntax#}. If {#syntax#}pred[i]{#endsyntax#} is {#syntax#}true{#endsyntax#}, the corresponding element in the result will be {#syntax#}a[i]{#endsyntax#} and otherwise {#syntax#}b[i]{#endsyntax#}. Selects values element-wise from {#syntax#}a{#endsyntax#} or {#syntax#}b{#endsyntax#} based on {#syntax#}pred{#endsyntax#}. If {#syntax#}pred[i]{#endsyntax#} is {#syntax#}true{#endsyntax#}, the corresponding element in the result will be {#syntax#}a[i]{#endsyntax#} and otherwise {#syntax#}b[i]{#endsyntax#}.
</p> </p>
@ -9252,7 +9252,7 @@ test "@setRuntimeSafety" {
{#header_close#} {#header_close#}
{#header_open|@shuffle#} {#header_open|@shuffle#}
<pre>{#syntax#}@shuffle(comptime E: type, a: std.meta.Vector(a_len, E), b: std.meta.Vector(b_len, E), comptime mask: std.meta.Vector(mask_len, i32)) std.meta.Vector(mask_len, E){#endsyntax#}</pre> <pre>{#syntax#}@shuffle(comptime E: type, a: @Vector(a_len, E), b: @Vector(b_len, E), comptime mask: @Vector(mask_len, i32)) @Vector(mask_len, E){#endsyntax#}</pre>
<p> <p>
Constructs a new {#link|vector|Vectors#} by selecting elements from {#syntax#}a{#endsyntax#} and Constructs a new {#link|vector|Vectors#} by selecting elements from {#syntax#}a{#endsyntax#} and
{#syntax#}b{#endsyntax#} based on {#syntax#}mask{#endsyntax#}. {#syntax#}b{#endsyntax#} based on {#syntax#}mask{#endsyntax#}.
@ -9287,22 +9287,21 @@ test "@setRuntimeSafety" {
</p> </p>
{#code_begin|test|vector_shuffle#} {#code_begin|test|vector_shuffle#}
const std = @import("std"); const std = @import("std");
const Vector = std.meta.Vector;
const expect = std.testing.expect; const expect = std.testing.expect;
test "vector @shuffle" { test "vector @shuffle" {
const a: Vector(7, u8) = [_]u8{ 'o', 'l', 'h', 'e', 'r', 'z', 'w' }; const a = @Vector(7, u8){ 'o', 'l', 'h', 'e', 'r', 'z', 'w' };
const b: Vector(4, u8) = [_]u8{ 'w', 'd', '!', 'x' }; const b = @Vector(4, u8){ 'w', 'd', '!', 'x' };
// To shuffle within a single vector, pass undefined as the second argument. // To shuffle within a single vector, pass undefined as the second argument.
// Notice that we can re-order, duplicate, or omit elements of the input vector // Notice that we can re-order, duplicate, or omit elements of the input vector
const mask1: Vector(5, i32) = [_]i32{ 2, 3, 1, 1, 0 }; const mask1 = @Vector(5, i32){ 2, 3, 1, 1, 0 };
const res1: Vector(5, u8) = @shuffle(u8, a, undefined, mask1); const res1: @Vector(5, u8) = @shuffle(u8, a, undefined, mask1);
try expect(std.mem.eql(u8, &@as([5]u8, res1), "hello")); try expect(std.mem.eql(u8, &@as([5]u8, res1), "hello"));
// Combining two vectors // Combining two vectors
const mask2: Vector(6, i32) = [_]i32{ -1, 0, 4, 1, -2, -3 }; const mask2 = @Vector(6, i32){ -1, 0, 4, 1, -2, -3 };
const res2: Vector(6, u8) = @shuffle(u8, a, b, mask2); const res2: @Vector(6, u8) = @shuffle(u8, a, b, mask2);
try expect(std.mem.eql(u8, &@as([6]u8, res2), "world!")); try expect(std.mem.eql(u8, &@as([6]u8, res2), "world!"));
} }
{#code_end#} {#code_end#}
@ -9329,7 +9328,7 @@ test "vector @shuffle" {
{#header_close#} {#header_close#}
{#header_open|@splat#} {#header_open|@splat#}
<pre>{#syntax#}@splat(comptime len: u32, scalar: anytype) std.meta.Vector(len, @TypeOf(scalar)){#endsyntax#}</pre> <pre>{#syntax#}@splat(comptime len: u32, scalar: anytype) @Vector(len, @TypeOf(scalar)){#endsyntax#}</pre>
<p> <p>
Produces a vector of length {#syntax#}len{#endsyntax#} where each element is the value Produces a vector of length {#syntax#}len{#endsyntax#} where each element is the value
{#syntax#}scalar{#endsyntax#}: {#syntax#}scalar{#endsyntax#}:
@ -9341,7 +9340,7 @@ const expect = std.testing.expect;
test "vector @splat" { test "vector @splat" {
const scalar: u32 = 5; const scalar: u32 = 5;
const result = @splat(4, scalar); const result = @splat(4, scalar);
comptime try expect(@TypeOf(result) == std.meta.Vector(4, u32)); comptime try expect(@TypeOf(result) == @Vector(4, u32));
try expect(std.mem.eql(u32, &@as([4]u32, result), &[_]u32{ 5, 5, 5, 5 })); try expect(std.mem.eql(u32, &@as([4]u32, result), &[_]u32{ 5, 5, 5, 5 }));
} }
{#code_end#} {#code_end#}
@ -9381,10 +9380,10 @@ const std = @import("std");
const expect = std.testing.expect; const expect = std.testing.expect;
test "vector @reduce" { test "vector @reduce" {
const value: std.meta.Vector(4, i32) = [_]i32{ 1, -1, 1, -1 }; const value = @Vector(4, i32){ 1, -1, 1, -1 };
const result = value > @splat(4, @as(i32, 0)); const result = value > @splat(4, @as(i32, 0));
// result is { true, false, true, false }; // result is { true, false, true, false };
comptime try expect(@TypeOf(result) == std.meta.Vector(4, bool)); comptime try expect(@TypeOf(result) == @Vector(4, bool));
const is_all_true = @reduce(.And, result); const is_all_true = @reduce(.And, result);
comptime try expect(@TypeOf(is_all_true) == bool); comptime try expect(@TypeOf(is_all_true) == bool);
try expect(is_all_true == false); try expect(is_all_true == false);
@ -9743,6 +9742,12 @@ fn foo(comptime T: type, ptr: *T) T {
{#syntax#}@unionInit{#endsyntax#} forwards its {#link|result location|Result Location Semantics#} to {#syntax#}init_expr{#endsyntax#}. {#syntax#}@unionInit{#endsyntax#} forwards its {#link|result location|Result Location Semantics#} to {#syntax#}init_expr{#endsyntax#}.
</p> </p>
{#header_close#} {#header_close#}
{#header_open|@Vector#}
<pre>{#syntax#}@Vector(len: comptime_int, Element: type) type{#endsyntax#}</pre>
<p>Creates {#link|Vectors#}.</p>
{#header_close#}
{#header_close#} {#header_close#}
{#header_open|Build Mode#} {#header_open|Build Mode#}

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@ -930,6 +930,7 @@ test "std.meta.Float" {
try testing.expectEqual(f128, Float(128)); try testing.expectEqual(f128, Float(128));
} }
/// Deprecated. Use `@Vector`.
pub fn Vector(comptime len: u32, comptime child: type) type { pub fn Vector(comptime len: u32, comptime child: type) type {
return @Type(.{ return @Type(.{
.Vector = .{ .Vector = .{

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@ -421,7 +421,7 @@ pub fn MultiArrayList(comptime S: type) type {
} }
fn capacityInBytes(capacity: usize) usize { fn capacityInBytes(capacity: usize) usize {
const sizes_vector: std.meta.Vector(sizes.bytes.len, usize) = sizes.bytes; const sizes_vector: @Vector(sizes.bytes.len, usize) = sizes.bytes;
const capacity_vector = @splat(sizes.bytes.len, capacity); const capacity_vector = @splat(sizes.bytes.len, capacity);
return @reduce(.Add, capacity_vector * sizes_vector); return @reduce(.Add, capacity_vector * sizes_vector);
} }