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combine getstringsingleton, getbooleansingleton

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Junseo Yoo 2024-07-31 10:58:20 -07:00
parent 40295408f1
commit a449a000c8
1 changed files with 7 additions and 14 deletions
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21
docs/user-defined-type-functions.md
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@ -89,13 +89,12 @@ Methods under a different heading (ex: Singleton) imply that the methods are onl
| Instance Methods | Return Type | Description | | Instance Methods | Return Type | Description |
| ------------- | ------------- | ------------- | | ------------- | ------------- | ------------- |
| `__eq(arg: type)` | `boolean` | overrides the == operator to return true if self is syntactically equal to arg | | `__eq(arg: type)` | `boolean` | overrides the == operator to return true if self is syntactically equal to arg |
| `is(arg: string)` | `boolean` | returns true if self has the same tag as the argument. List of available tags: "nil", "unknown", "never", "any", "boolean", "number", "string", "boolean singleton", "string singleton", "negation", "union", "intersection", "table", "function", "class" | | `is(arg: string)` | `boolean` | returns true if self has the same tag as the argument. List of available tags: "nil", "unknown", "never", "any", "boolean", "number", "string", "singleton", "negation", "union", "intersection", "table", "function", "class" |
| Static Methods | Return Type | Description | | Static Methods | Return Type | Description |
| ------------- | ------------- | ------------- | | ------------- | ------------- | ------------- |
| `getnegation(arg: type)` | `type` | returns an immutable runtime representation of the argument as a negated type; the argument cannot be an instance of a table or a function | | `getnegation(arg: type)` | `type` | returns an immutable runtime representation of the argument as a negated type; the argument cannot be an instance of a table or a function |
| `getstringsingleton(arg: string)` | `type` | returns an immutable runtime representation of the argument as a string singleton type | | `getsingleton(arg: string \| boolean)` | `type` | returns an immutable runtime representation of the argument as a singleton type |
| `getbooleansingleton(arg: boolean)` | `type` | returns an immutable runtime representation of the argument as a boolean singleton type |
| `getunion(...: type)` | `type` | returns an immutable runtime representation of an union type of the arguments; requires the arguments size to be at least 2 | | `getunion(...: type)` | `type` | returns an immutable runtime representation of an union type of the arguments; requires the arguments size to be at least 2 |
| `getintersection(...: type)` | `type` | returns an immutable runtime representation of an intersection type of the arguments | | `getintersection(...: type)` | `type` | returns an immutable runtime representation of an intersection type of the arguments |
| `newtable(props: {[type]: type}?, indexer: {key: type, value: type}?, metatable: type?)` | `type` | returns a mutable runtime representation of a table type; the keys of the table's property must be a runtime representation of the singleton types; if provided the metatable parameter, this table becomes a metatable | | `newtable(props: {[type]: type}?, indexer: {key: type, value: type}?, metatable: type?)` | `type` | returns a mutable runtime representation of a table type; the keys of the table's property must be a runtime representation of the singleton types; if provided the metatable parameter, this table becomes a metatable |
@ -108,17 +107,11 @@ Methods under a different heading (ex: Singleton) imply that the methods are onl
| ------------- | ------------- | ------------- | | ------------- | ------------- | ------------- |
| `gettype()` | `type` | returns the `type` being negated | | `gettype()` | `type` | returns the `type` being negated |
#### StringSingleton #### Singleton
| Instance Methods | Return Type | Description | | Instance Methods | Return Type | Description |
| ------------- | ------------- | ------------- | | ------------- | ------------- | ------------- |
| `getvalue()` | `string` | returns the string value of the string singleton | | `getvalue()` | `string \| boolean` | returns the string value of the singleton |
#### BooleanSingleton
| Instance Methods | Return Type | Description |
| ------------- | ------------- | ------------- |
| `getvalue()` | `boolean` | returns the boolean value of the boolean singleton |
#### Table #### Table
@ -174,10 +167,10 @@ Enforcing time limits on type functions is quite problematic for the same reason
### Table Runtime Representation ### Table Runtime Representation
Instead of serializing types into `type`, we can serialize them into tables with predefined properties. For instance, the representation for a string singleton `"abc"` could be `{type = "string singleton", value = "abc"}`. So instead of writing: Instead of serializing types into `type`, we can serialize them into tables with predefined properties. For instance, the representation for a string singleton `"abc"` could be `{type = "singleton", value = "abc"}`. So instead of writing:
```luau ```luau
type function issingleton(t) type function issingleton(t)
if t:is("string singleton") then if t:is("singleton") then
return t return t
end end
end end
@ -185,7 +178,7 @@ end
developers could write: developers could write:
```luau ```luau
type function issingleton(t) type function issingleton(t)
if t.type == "string singleton" then if t.type == "singleton" then
return t return t
end end
end end