Documentation

Compute the first character of a type-level symbol

>>> :kind! Head "Example"
Head "Example" :: Symbol
= "E"

>>> :kind! Head ""
Head "" :: Symbol
= ""

Head doesn't fail if the first character is ASCII, rest is irrelevant

>>> :kind! Head "123±456"
Head "123±456" :: Symbol
= "1"

Head fails if the first character is non-ASCII

>>> :kind! Head "±123"
Head "±123" :: Symbol
= (TypeError ...)

Convert the symbol into a list of characters

>>> :kind! ToList "ABC"
ToList "ABC" :: [Symbol]
= '["A", "B", "C"]

ToList works only for ASCII strings

>>> :kind! ToList "123±456"
ToList "123±456" :: [Symbol]
= "1" : "2" : "3" : (TypeError ...)

Convert the symbol to uppercase

Convert the symbol to lowercase

Parse a natural number