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# Erlang zlist: a lazy sequences library.
----------------------------------------------------
## Description ##
Unlike https://github.com/vjache/erlang-zlists
zlist() is a function that returns improper list with data and next zlist or
an empty list.
You can use it to organize lazy evolution or backpressure.
Simple infinite iterator:
```erlang
1> SimpleZ = fun Loop() -> [1|Loop] end.
#Fun<erl_eval.44.90072148>
2> zlist:take(10, SimpleZ).
{[1,1,1,1,1,1,1,1,1,1],#Fun<erl_eval.62.90072148>}
```
## Usage ##
### Integrate to your project ###
This is a rebar'ized project, so, if you are already using rebar, just insert a reference
to this git repo at your rebar.config.
### Examples ###
```erlang
1> Z = zlist:recurrent(fun(A) -> A + 1 end, 0).
#Fun<zlist.14.21462417>
2> zlist:take(10, Z).
{[1,2,3,4,5,6,7,8,9,10],#Fun<zlist.14.21462417>}
3> Z2 = zlist:map(fun(A) -> A * 2 end, Z).
#Fun<zlist.3.21462417>
4> zlist:take(10, Z2).
{[2,4,6,8,10,12,14,16,18,20],#Fun<zlist.3.21462417>}
5> ZL = zlist:from_list([1,2,5]).
#Fun<zlist.12.21462417>
6> zlist:to_list(ZL).
[1,2,5]
7> ZR = zlist:ciclyc(ZL).
#Fun<zlist.17.21462417>
8> zlist:take(10, ZR).
{[1,2,5,1,2,5,1,2,5,1],#Fun<zlist.17.21462417>}
9> Z3 = zlist:flatmap(fun(A) -> zlist:from_list([-A, A]) end, Z2).
#Fun<zlist.6.21462417>
10> zlist:take(10, Z3).
{[-2,2,-4,4,-6,6,-8,8,-10,10],#Fun<zlist.10.21462417>}
```
### Warnings !!! ###
With zlist you are working with potentially infinite data.
Don't use ```to_list/1```, ```foreach/2```, ```fold/3``` functions
until you know that zlist is finite state.
Use ```dropwhen/1``` before, or ```take/2``` instead.
