A regexp for an include? method

[Boucher, Eric]

Hi,

I want to see if a certain pattern is inside an array. I tried:
myArray.flatten.include?(/myPattern/)

but it always return false. Why? Is it because the "include?" doesn't takes
regular expressions?
Here's another example that I tried inside an irb session:

data = ["TC_TP1", "TC_TP2", "TC_TP3"]
=>["TC_TP1", "TC_TP2", "TC_TP3"]
data.include?(/TC_TP/)
=> false
data.include?(/TC_TP.*/)
=> false
data.include?(/TC_TP1/)
=> false
data.include?("TC_TP1")
=> true !!!

Thanks for your help.

 

[Robert Klemme]

Hi,

I want to see if a certain pattern is inside an array. I tried:
myArray.flatten.include?(/myPattern/)

but it always return false. Why? Is it because the "include?" doesn't
takes regular expressions?
Here's another example that I tried inside an irb session:

data = ["TC_TP1", "TC_TP2", "TC_TP3"]
=>["TC_TP1", "TC_TP2", "TC_TP3"]
data.include?(/TC_TP/)
=> false
data.include?(/TC_TP.*/)
=> false
data.include?(/TC_TP1/)
=> false
data.include?("TC_TP1")
=> true !!!

Thanks for your help.

It's because include? uses #eql? or == for comparison while regexp matching
is done via === and =~. You can use #find, #select or #any?

irb(main):042:0> data.find {|x| /TC_TP/ =~ x}
=> "TC_TP1"
irb(main):043:0> data.find {|x| /XTC_TP/ =~ x}
=> nil
irb(main):044:0> data.select {|x| /XTC_TP/ =~ x}
=> []
irb(main):045:0> data.select {|x| /TC_TP/ =~ x}
=> ["TC_TP1", "TC_TP2", "TC_TP3"]
irb(main):046:0> data.any? {|x| /TC_TP/ =~ x}
=> true
irb(main):047:0> data.any? {|x| /YTC_TP/ =~ x}
=> false

I'd go for any? as it short circuits, i.e. terminates after the first
successful match.

Kind regards

robert

 

[semmons99]

What about using:
data.match(/TC_TP/)
should return nil if it doesn't match, otherwise returns the matching
string.

 

[Robert Klemme]

What about using:
data.match(/TC_TP/)
should return nil if it doesn't match, otherwise returns the matching
string.

It doesn't return the matching string but an object of type MatchData. The
matched string can be extracted from that. Another form is to use String#[]
with regexp, like

arr.any? {|s| s[/TC_TP/]}

Kind regards

robert

 

[William James]

Hi,

I want to see if a certain pattern is inside an array. I tried:
myArray.flatten.include?(/myPattern/)

but it always return false. Why? Is it because the "include?" doesn't takes
regular expressions?
Here's another example that I tried inside an irb session:

data = ["TC_TP1", "TC_TP2", "TC_TP3"]
=>["TC_TP1", "TC_TP2", "TC_TP3"]
data.include?(/TC_TP/)
=> false
data.include?(/TC_TP.*/)
=> false
data.include?(/TC_TP1/)
=> false
data.include?("TC_TP1")
=> true !!!

Thanks for your help.

myArray.flatten.grep(/myPattern/)