How to use the ruby ​​"case ... when" with inequality?

Question

can you do it in ruby? he seems to “skip” cases with inequalities

case myvar when myvar < -5 do somethingA when -5..-3 do special_something_XX when -2..-1 do special_something_YY when myvar == 0 do somethingB when myvar > 0 go somethingC end 

Answer 1

You mix two different types of case statements:

 case var when 1 dosomething when 2..3 doSomethingElse end case when var == 1 doSomething when var < 12 doSomethingElse end 

Answer 2

  case myvar when proc { |n| n < -5 } do somethingA when -5..-3 do special_something_XX when -2..-1 do special_something_YY when proc { |n| n == 0 } do somethingB when proc { |n| n > 0 } go somethingC end end 

Answer 3

I’m personally not sure if you’d better not work with if statements, but if you want to find a solution in this form:

 Inf = 1.0/0 case myvar when -Inf..-5 do somethingA when -5..-3 do special_something_XX when -2..-1 do special_something_YY when 0 do somethingB when 0..Inf do somethingC end 

The following is my decision. Here, the order matters, and you need to repeat myvar , but it’s much harder not to take cases into account, you don’t need to repeat each binding twice, and the rigor ( < vs <= , not .. vs ... ) is much more obvious.

 if myvar <= -5 # less than -5 elsif myvar <= -3 # between -5 and -3 elsif myvar <= -1 # between -3 and -1 elsif myvar <= 0 # between -1 and 0 else # larger than 0 end 

Answer 4

 def project_completion(percent) case percent when percent..25 "danger" when percent..50 "warning" when percent..75 "info" when percent..100 "success" else "info" end end 

Answer 5

Using infinity may help

 case var when -Float::INFINITY..-1 when 0 when 1..2 when 3..Float::INFINITY end