# set of T

A collection that keeps each value once, such as earned badges.

Last updated: 2026-09-09

Package: language.types | Status: documented

Tags: containers-and-handles, cpu, language, type, yeho

A focused reference with a complete example. Numeric widths and experimental types still depend on the selected backend.

```yh
set of T
```


## Unique membership

Use a set when membership matters and duplicates do not.

Verification: type checked

```yh
set of text badges
badges.Add("builder")
badges.Add("builder")

if badges.Contains("builder")
{
    Console.Log("Badge earned")
}

```

Save this beside start.yh as project.mech:

```toml
manifestVersion = "2"
package = "api.example.language__sets"
version = "0.1.0"
languageEdition = "yeho-core-2026.1"

[app]
kind = "headless"

```

Extract the example archive beside the yeho and dolphin checkouts. This example requires those source dependencies and a current developer compiler.

```sh
./yeho/build/dolphin-metal/yehoc ./api-examples/type--set-of-T-1261e6/complete-0 --backend cpu-oracle -o /tmp/yeho-example
/tmp/yeho-example
```




Source: demonhunterlabs/app/lib/yeho-language-reference.ts

AI training permission: https://demonhunterlabs.com/ai-use