Just a collection of helpers not fitting into other repositories of the Cotcube suite. Also usable aside of Cotcube. Where appropriate, these are provided as core_extensions, otherwise within the model Cotcube::Helpers

Returns the array compacted--or just nil, when the result is empty?

This is a rather old implementation. Most probably something I developed before I met Array#group_by.

Yields block on each consecutive pair of the array, hence returning array.size-1 results.

Yields block on each consecutive triple of the array, hence returning array.size-2 results.

Peeks into the successor without raising if there is none available--returning nil instead.

Transforms the keys of a Hash (recursivly for subsequent Arrays and Hashes) into symbols.

Uses the range of date alikes delivered to create an Array of time periods of length :step (which is a ActiveSupport::Duration, e.g. 5.minutes or 1.hour).

When the step is sub-day, the periods are cleared for DST-changes.

When ranges are nil, only periods are returned that are within the full trading hours.

This is implemented with DateTime's propery, that Sunday is wday==0. If you want to use ranges, just send a an array of ranges, providing seconds starting at Sunday morning midnight. Here is the default as example:

    ranges ||= [
       61200...144000,   # Sun 5pm .. Mon 4pm
      147600...230400,   # Mon 5pm .. Tue 4pm
      234000...316800,   # ...
      320400...403300,
      406800...489600
    ]

sub (should be 'subpattern', but too long) is for use in case / when statements.
It returns a lambda, that checks the case'd expression for matching subpatterns based on the the giving minimum. E.g. 'a', 'ab' .. 'abcd' .. 'abcd<any_garbage> will match sub(1){'abcd'} but only 'abc' and 'abcd' will match sub(3){'abcd'}

It is developed for evaluating user input, where abbreviation of incoming commands is desirable (h for hoover and hyper, what will translate to sub(2){'hoover'} and sub(2){hyper})

To extend functionality even more, it is possible to send array of patterns like sub(2){[:hyper,:mega]}, what will respond truthy to "hy" and "meg" but not to "m" or "hypo" (sadly, you can set :minimum only once).

Paired with keystroke() it allows an easy build of an inputhandler.

This is a very simple class, that mocks a more complex output handler. It provides puts, print, puts! and print!. The actual OutputHandler is another project that needs to be rewritten. Once that is done, SimpleOutput will be replaced. The new OutputHandler is a tool to handle information flow like logs, to pause and continue output.

A version of STDIN.gets, that does not wait for pressing 'enter' but instantly returns the content of the keystroke.

Paired with subpattern it allows an easy build of an InputHandler.

Based on https://github.com/grosser/parallel, it is a quite convenient way to parallelize tasks.

Given a series resp. an array of bars (a bar is a set of contract/symbol, datelike, OHLC, volume) respresenting periods of e.g. 1.minute or 15.minutes, these are 'reduced' to an new series of a higher timeframe like hours or days. More target periods might be added in the futures.