Arrays and pure functions

array-and-pure.kawaii

from fs      import readFile as read
from console import print

async main () : I32
    let raw    = (await read('array.txt')).toString()
    let split  = raw.split('\n')
    let mapper = pure (line, number) # `line`'s type inferred as `String`
        'Line #`number + 1`: `line`'
        #
            No `return` keyword
            Value of latest expression used as return value instead
            However, it's subject of change, I'm pretty unsure of this design

        # Also I'm unsure of syntax of passing functions as arguments
        
        #
            NB: Pure functions on arrays may be executed in parallel in different threads.
            Should I return a Promise from `map` methon in this case?
            Or it will be blocking operating and current thread
            will wait until map function will be executed on every array item?

        #
            Oh, for multiline comments can be used exactly the same syntax as for single-line,
            but subsequent lines must be indented relatively to the first comment line.

    let mapped = split.map(mapper)
    print('`mapped.join('\n')`')