Module my_lists

Copyright © 2003 - 2004 Enrique Marcote Peña

• Description
• Function Index
• Function Details

Version: 1.0, {19 Feb 2003} 12:29:46.

Authors: Enrique Marcote Peña (mpquique@users.sourceforge.net) [web site: http://www.des.udc.es/~mpquique/].

Description

Additional functions for list processing.

Changes 0.2 -> 1.0

• New functions: first/2, is_deep/1, keyindex/3 and splitwith/2.

Function Index

Function Details

asearch/2

asearch(APred::APred, List::List) -> Result

• List = [term()]
• Result = {value, Element} | false
• Element = term()

Gets the first Element on the List where APred(Element) /= false.

• APred = fun(X) -> true | approximate | false

APred is an approximate predicate that returns true, false or approximate.

If matching is ambiguous, there is more than one element on the list where the approximate-predicate returns approximate, false is returned. This behaviour may be changed in the future returning the atom ambiguous is such circumstances.

See also: my_string:aequal/2, my_string:aequal/6.

cut/2

cut(List::List, Index::Index) -> {Prefix, Suffix}

• List = [term()]
• Index = int()
• Prefix = [term()]
• Suffix = [term()]

Cuts a List by an Index into two sublists. Prefix ++ Suffix == List.

> my_lists:cut([a, b, c, d, e], 3).
{[a, b, c], [d, e]}

first/2

first(Pred::Pred, T::List) -> Element

• List = [Element]
• Element = term()

Gets the first Element of List where Pred is true.

This function fails if no element on List satisfies Pred.

has_duplicates/1

has_duplicates(T::List) -> bool()

• List = term()

Determines if a list has duplicates or not.

is_deep/1

is_deep(T::List) -> bool()

• List = [Element]
• Element = term()

Returns true if List is a deep list, false otherwise.

keyindex/3

keyindex(Key::Key, N::N, TupleList::TupleList) -> Index

Gets the Index of the tuple on TupleList whose Nth element is Key.

The functions fails if no element with such a Key exists on TupleList.

random/2

random(Max::Max, Length::Length) -> List

• Max = int()
• Lenght = int()
• List = [int()]

Creates a list of random integers with Length elementes.

Duplicates allowed, the values will be between 1 and Max (both included).

See also: random_seq/2.

random_seq/2

random_seq(Max::Max, Length::Length) -> List

• Max = int()
• Lenght = int()
• List = [int()]

Creates an ordered list of random integers with Length elements.

No duplicates allowed, the values will be between 1 and Max (both included).

See also: random/2, random_add/3, random_del/3.

search/2

search(Pred::Pred, T::List) -> Result

• List = [term()]
• Result = {value, Element} | false
• Element = term()

Gets the first Element on the List where Pred(Element) == true.

• Pred = fun(X) -> bool()

split/2

split(List::List, N::N) -> {List1, List2}

• List = [Element]
• List1 = [Element]
• List2 = [Element]
• Element = term()
• N = int()

Splits a List into two lists where
List == List1 ++ List2 and length(List1) == N.

I couldn't find it, but I'm sure this function must already exist.

splitwith/2

splitwith(Pred::Pred, L::List) -> {List1, List2}

• List = [term()]
• List1 = [term()]
• List2 = [term()]

Splits a List into two lists where elements on List1 satisfy Pred. List2 holds the elements for which Pred is false.

• Pred = fun(X) -> bool()

Ordering is preserved.

to_integer/1

to_integer(OctetList::OctetList) -> int()

• OctetList = [Octet]
• Octet = char()

Converts a list of octets to an integer.

Please notice the difference:

48> my_lists:to_integer("100").
3223600
49> list_to_integer("100").
100
50> my_lists:to_integer("F").
70
51> list_to_integer("F").
=ERROR REPORT==== 21-Mar-2003::12:38:43 ===
Error in process <0.118.0> with exit value: {badarg,
[{erlang,list_to_integer,["F"]},{erl_eval,expr,3},{erl_eval,exprs,4},
{shell,eval_loop,2}]}
** exited: {badarg,[{erlang,list_to_integer,["F"]},
{erl_eval,expr,3},
{erl_eval,exprs,4},
{shell,eval_loop,2}]} **

See also: list_to_integer/1.