CODEWITHSUNDEEP
arraysrubyselect
Rojj
Rojj

Reputation: 1220

Select elements of array with arbitrary number of criteria

I have an array of Time objects. I want my user to be able to select a subset of elements based on various criteria. The number of criteria is unknown and it can vary. Also, I would like to add additional criteria in the future if needed.

If ts is the array, I can write:

ts.select{|t| (t.hour == 12 || t.hour == 16) && t.month == 3}

but how I could make this generic so that each method of Time could potentially be used for filtering? For example, the UI could generate a Hash:

{:hour => [12, 16], :month => [3]}

and this should be used to create the final filter combining all the conditions.

For each method I can have only OR conditions and between methods only AND conditions. For example the typical query would return all the time for Summer afternoons. So {:month => [6, 7, 8, 9], :hour => [12,13,14,15,16,17]}

Upvotes: 0

Views: 42

Answers (1)

sawa
sawa

Reputation: 168199

{:hour => [12, 16], :month => [3]}
.inject(ts){|ts, (k, v)| ts.select{|t| v.include?(t.send(k))}}

Upvotes: 2

Related Questions