Search in string with regular expression

[Micke Micke]

Hi all

I'm trying to build a new string from a existing one.

The original string is: my frog name is froggy
I will pull out only: frog froggy

I have tried the following:
----

str1 = 'my frog name is froggy'
str2 = str1[/frog|froggy/]

puts str2

---

This will print only the string: frog

I can get the information with this code:
----

str1 = 'my frog name is froggy'
str2 = str1[/frog] + " " + str1[/froggy/]

puts str2
----

This will print the string: frog froggy
But i think it is possible to solve this in a better way, Any
suggestions ?


// Micke

 

[Li Chen]

Hi all

I'm trying to build a new string from a existing one.

The original string is: my frog name is froggy
I will pull out only: frog froggy

C:\Users\Alex>irb
irb(main):001:0> str1 = 'my frog name is froggy'
=> "my frog name is froggy"
irb(main):002:0> str2=str1.scan( /froggy|frog/ )
=> ["frog", "froggy"]
irb(main):003:0> str3=str1.scan( /frog|froggy/ )
=> ["frog", "frog"]
irb(main):004:0>


Li

 

[Robert Dober]

Hi all

I'm trying to build a new string from a existing one.

The original string is: my frog name is froggy
I will pull out only: frog froggy

I have tried the following:

Maybe
str2 =3D str1.scan( /\bfrog\w*\B/ ).join(" ")
that is if you want to match frog at the start of words only (\b) and
assure charcters of your choice up to the end of the word? As \w might
be a little bit too permissive, in 1.9 you might prefer
str2 =3D str1.scan( /\bfrog[[:alpha:]]*\B/ ).join(" ")
and all those nice variations

HTH
Robert

puts str2

---

This will print only the string: frog

I can get the information with this code:
----

str1 =3D 'my frog name is froggy'
str2 =3D str1[/frog] + " " + str1[/froggy/]

puts str2
----

This will print the string: frog froggy
But i think it is possible to solve this in a better way, Any
suggestions ?


// Micke

--=20
Toutes les grandes personnes ont d=92abord =E9t=E9 des enfants, mais peu
d=92entre elles s=92en souviennent.

All adults have been children first, but not many remember.

[Antoine de Saint-Exup=E9ry]

 

[Harry Kakueki]

Maybe

=A0str2 =3D str1.scan( /\bfrog\w*\B/ ).join(" ")
that is if you want to match frog at the start of words only (\b) and
assure charcters of your choice up to the end of the word? As \w might
be a little bit too permissive, in 1.9 you might prefer
=A0 str2 =3D str1.scan( /\bfrog[[:alpha:]]*\B/ ).join(" ")
and all those nice variations

HTH
Robert

Or maybe,

str2 =3D str1.scan( /\bfrog\w*\b/ ).join(" ")

Harry

--=20
A Look into Japanese Ruby List in English
http://www.kakueki.com/ruby/list.html

 

[Robert Dober]

Maybe
str2 =3D str1.scan( /\bfrog\w*\B/ ).join(" ")
that is if you want to match frog at the start of words only (\b) and
assure charcters of your choice up to the end of the word? As \w might
be a little bit too permissive, in 1.9 you might prefer
str2 =3D str1.scan( /\bfrog[[:alpha:]]*\B/ ).join(" ")
and all those nice variations

HTH
Robert

Or maybe,

str2 =3D str1.scan( /\bfrog\w*\b/ ).join(" ")

No it was not a typo, I thought that \B was matching at the end of the
word, I did not test with a frog at the end.
I stand corrected \B does not have a special meaning and \b is just a
word boundary.

Thx
Robert

A Look into Japanese Ruby List in English
http://www.kakueki.com/ruby/list.html

--=20
Toutes les grandes personnes ont d=92abord =E9t=E9 des enfants, mais peu
d=92entre elles s=92en souviennent.

All adults have been children first, but not many remember.

[Antoine de Saint-Exup=E9ry]

 

[Robert Dober]

Maybe
str2 = str1.scan( /\bfrog\w*\B/ ).join(" ")
that is if you want to match frog at the start of words only (\b) and
assure charcters of your choice up to the end of the word? As \w might
be a little bit too permissive, in 1.9 you might prefer
str2 = str1.scan( /\bfrog[[:alpha:]]*\B/ ).join(" ")
and all those nice variations

HTH
Robert

Or maybe,

str2 = str1.scan( /\bfrog\w*\b/ ).join(" ")

No it was not a typo, I thought that \B was matching at the end of the
word, I did not test with a frog at the end.
I stand corrected \B does not have a special meaning and \b is just a
word boundary.

I mean \B is not a word boundary and \b is a word boundary and I
wonder WHAT I did test???
Sorry
R.

 

[David A. Black]

Hi --

Maybe
str2 = str1.scan( /\bfrog\w*\B/ ).join(" ")
that is if you want to match frog at the start of words only (\b) and
assure charcters of your choice up to the end of the word? As \w might
be a little bit too permissive, in 1.9 you might prefer
str2 = str1.scan( /\bfrog[[:alpha:]]*\B/ ).join(" ")
and all those nice variations

HTH
Robert

Or maybe,

str2 = str1.scan( /\bfrog\w*\b/ ).join(" ")

No it was not a typo, I thought that \B was matching at the end of the
word, I did not test with a frog at the end.
I stand corrected \B does not have a special meaning and \b is just a
word boundary.

\B is the opposite of \b, i.e., "not at a word boundary". So:

/\B./.match("word")[0]

=> "o"


David

--
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