10.4.3  lower-case identifiers

Mythryl uses lower-case identifiers to name constants, variables, functions and packages. Their syntax is:

    [a-z][a-z'_0-9]*

Note in particular that apostrophe is a legal constituent of such identifier names. As in mathematics, a trailing apostrophe is often used to mark a slight variant of a variable:

    foo                 # Some value.
    foo'                # Closely related value.

Some lower-case identifiers are reserved and not available for programmer use as vanilla identifiers:

    abstype
    also
    and
    api
    as
    case
    class
    elif
    else
    end
    eqtype
    esac
    except
    exception
    fi
    fn
    for
    fprintf
    fun
    herein
    if
    include
    my
    or
    package
    printf
    sharing
    sprintf
    stipulate
    val
    where
    with
    withtype