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Go-style built-ins

Gsharp.Extensions.Go also surfaces the small set of Go-style built-in functions — len, cap, append, and delete — that work uniformly across arrays, slices, 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}
Console.WriteLine(len(nums))   // 3
Console.WriteLine(cap(nums))   // 3
Console.WriteLine(len("hello")) // 5

The .NET-idiomatic spelling without the extension import is nums.Length, "hello".Length, and so on. 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​