Module ListExtras

module ListExtras: sig  end

Utility functions for dealing with lists

Searching

val index : 'a -> 'a list -> int

index item list returns the 0-based position of index in list.
Raises Not_found if the item isn't in list.

val indexq : 'a -> 'a list -> int

Same as index but using physical equality instead of structural equality to compare the elements.

Complex equality

The following functor provides list functions that compare items of lists in terms of a user-defined equality function rather than the built-in = or == operators.

module type ComparableType = sig  end

Input signature of the functor ListExtras.Make.

module type S = sig  end

Output signature of the functor ListExtras.Make

module Make: functor (Comp : ComparableType) -> sig  end

Sorting

val munge : cmp:('a -> 'a -> int) -> f:('b -> 'a) -> 'b list -> 'b list

Implements munging/Schwartzian transform on a list. Maps 'a list to 'b list and returns the original 'a list ordered by a sort of 'b list.

val stable_munge : cmp:('a -> 'a -> int) -> f:('b -> 'a) -> 'b list -> 'b list

The same using a stable sort

val fast_munge : cmp:('a -> 'a -> int) -> f:('b -> 'a) -> 'b list -> 'b list

The same using the fastest list sorting

Extracting elements

These are lifted from scheme.

val car : 'a list -> 'a

Same as List.hd

val cdr : 'a list -> 'a list

Same as List.tl

val cadr : 'a list -> 'a

val cddr : 'a list -> 'a list

val caddr : 'a list -> 'a

val cdddr : 'a list -> 'a list

val cadddr : 'a list -> 'a

val cddddr : 'a list -> 'a list

val tail : 'a list -> int -> 'a list

Returns the nth cdr (Zero-based) of list