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Version: 0.4

Go-style built-ins

Gsharp.Extensions.Go also surfaces the small set of Go-style built-in functions — len, cap, append, and delete — that cover fixed, rectangular, and slice arrays plus strings and maps. Outside this extension namespace the .NET-idiomatic spelling is preferred (.Length, .Count, List[T].Add, Dictionary[K,V].Remove); the built-ins are available when a Go-shaped codebase wants them.

:::note Requires import Gsharp.Extensions.Go The built-ins are gated behind a per-file import Gsharp.Extensions.Go. Without the import, the binder emits GS0317 for each use; the message names the .NET-idiomatic alternative (.Length, .Count, .Remove(k), List[T].Add) when one exists. :::

Length and capacity — len / cap​

len(x) returns the count of elements (or characters, for strings) and cap(x) returns the underlying capacity for slice-shaped values.

import System
import Gsharp.Extensions.Go

var nums = []int32{10, 20, 30}
var matrix = [2, 3]int32
Console.WriteLine(len(nums))   // 3
Console.WriteLine(cap(nums))   // 3
Console.WriteLine(len(matrix)) // 6 (total rectangular element count)
Console.WriteLine(len("hello")) // 5

The .NET-idiomatic spelling without the extension import is nums.Length, matrix.Length, "hello".Length, and so on. Rectangular arrays also expose .Rank and .GetLength(d). cap and append do not apply to rectangular arrays. Maps spell their count as .Count.

Append — append​

append(slice, value) returns a new []T containing the appended value. The first argument must be []T; the second converts to T.

import System
import Gsharp.Extensions.Go

var nums = []int32{1, 2, 3}
nums = append(nums, 4)
Console.WriteLine(nums[3])   // 4

For mutable, grow-and-copy semantics the .NET-idiomatic alternative is List[T] plus .Add.

Delete — delete​

delete(map, key) removes a key from a map.

import System
import Gsharp.Extensions.Go

var counts = map[string,int32]{"a": 1, "b": 2}
delete(counts, "a")
Console.WriteLine(len(counts))  // 1

The .NET-idiomatic alternative is Dictionary[K,V].Remove(key).

See also​