// is-absolute("/foo") => True
// is-absolute("bar/baz") => False
define is-absolute(path: &text): bool
// is-absolute("/foo") => False
// is-absolute("bar/baz") => True
define is-relative(path: &text): bool
// clean("foo/./bar//../buz.txt") => "foo/buz.txt"
define clean(path: &text): text
// append("test/sample", "foo.txt") => "test/sample/foo.txt"
// append("test/sample/", "foo.txt") => "test/sample/foo.txt"
// append("test/sample", "/foo.txt") => "test/sample/foo.txt"
// append("test/sample/", "/foo.txt") => "test/sample/foo.txt"
// append("test/.//sample/", "/foo.txt") => "test/sample/foo.txt"
define append(path1: &text, path2: &text): text
// take-last("test/sample/foo.txt") => "foo.txt"
// take-last("test/.//sample/foo.txt") => "foo.txt"
// take-last("test/sample/") => ""
define take-last(path: &text): text
// drop-last("test/sample/foo.txt") => "test/sample"
// drop-last("test/.//sample/foo.txt") => "test/sample"
// drop-last("test/sample/") => "test/sample"
define drop-last(path: &text): text
// split-extension("test/sample/foo.txt") => Pair("test/sample/foo", ".txt")
// split-extension("test/.//sample/foo.txt") => Pair("test/sample/foo", ".txt")
// split-extension("test/sample/foo") => Pair("test/sample/foo", "")
// split-extension("test/sample/.foo") => Pair("test/sample/.foo", "")
// split-extension("test/sample/.foo.tar.gz") => Pair("test/sample/.foo.tar", ".gz")
define split-extension(path: &text): pair(text, text)