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121 lines
No EOL
2.7 KiB
Markdown
121 lines
No EOL
2.7 KiB
Markdown
# functions
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## basic functions
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### if|T; U|(cond: Bool, then: T, else: U) -> T or U
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### map|T; U|(i: Iterable T, f: T -> U) -> Map U
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Note that the order of arguments is reversed from Python.
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### log(x: Object, type: LogType = Info) -> None
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Log `x` in debug display. Logs are summarized and displayed after the execution is finished.
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Emoji-capable terminals are prefixed according to `type`.
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* type == Info: 💬
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* type == Ok: ✅
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* type == Warn: ⚠️
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* type == Hint: 💡
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### panic(msg: Str) -> Panic
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Display msg and stop.
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Emoji-capable terminals have a 🚨 prefix.
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### discard|T|(x: ...T) -> NoneType
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Throw away `x`. Used when the return value is not used. Unlike `del`, it does not make the variable `x` inaccessible.
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```python
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p!x=
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# Let q! return some None or non-() value
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# use `discard` if you don't need it
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discard q!(x)
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f x
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discard True
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assert True # OK
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```
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### import(path: Path) -> Module or CompilerPanic
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Import a module. Raises a compilation error if the module is not found.
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### eval(code: Str) -> Object
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Evaluate code as code and return.
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### classof(object: Object) -> Class
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Returns the class of `object`.
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However, since classes cannot be compared, use `object in Class` instead of `classof(object) == Class` if you want to judge instances.
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The structure type determined at compile time is obtained with `Typeof`.
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## Iterator, Array generation system
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### repeat|T|(x: T) -> RepeatIterator T
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```python
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rep = repeat 1 # Repeater(1)
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for! rep, i =>
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print!i
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# 1 1 1 1 1 ...
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```
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### dup|T; N|(x: T, N: Nat) -> [T; N]
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```python
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[a, b, c] = dup new(), 3
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print! a # <Object object>
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print! a == b # False
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```
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### cycle|T|(it: Iterable T) -> CycleIterator T
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```python
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cycle([0, 1]).take 4 # [0, 1, 0, 1]
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cycle("hello").take 3 # "hellohellohello"
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```
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## constant expression functions
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### Class
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Create a new class. Unlike `Inherit`, passing through `Class` is independent of the base type and methods are lost.
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You won't be able to compare, but you can do things like pattern matching.
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```python
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C = Class {i = Int}
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NewInt = ClassInt
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Months = Class 1..12
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jan = Months.new(1)
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jan + Months.new(2) # TypeError: `+` is not implemented for 'Months'
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match jan:
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1 -> log "January"
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_ -> log "Other"
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```
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The second argument, Impl, is the trait to implement.
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### Inherit
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Inherit a class. You can use the base class methods as they are.
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### Traits
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Create a new trait. Currently, only record types can be specified.
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### Type of
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Returns the argument type. Use `classof` if you want to get the runtime class.
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If you use it for type specification, Warning will appear.
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```python
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x: Type of i = ...
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# TypeWarning: Typeof(i) == Int, please replace it
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```
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### Deprecated
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Use as a decorator. Warn about deprecated types and functions. |