Yukihiro - Please ensure backwards compatibility

[Joseph Benik]

having recently migrated one of my machines from a 1.6 flavor to the
new 1.8 i must say i was surprised to see problems with


blah.gsub!("testing", ' ')



i got a message that it was going to ignore(?) this statement as
"testing" was not a regexp..... this hit me on more than one script,
forcing me into a quick-fix mode as i definitely was not anticipating
this script-debilitating "ignore" of my code...


i don't understand the need to nitpick the regexp in this case, if
someone passes a string it seems quite a simple task for you to
_ENSURE BACKWARDS COMPATIBILITY_ and convert it internally to a regexp

 

[Elias Athanasopoulos]

This is a deprecation warning. It will no longer be backwards compatible in
1.9 and later, IIRC (maybe as early as 1.8.1).

In 1.8.0, however, it's just a warning.

I had this "problem", too. I can't see why Ruby is so verbose on that
and doesn't interpret foo.gsub[!]("bar", ...) as foo.gsub[!](/bar/, ...)
automagically...

Regards,

 

[Ara.T.Howard]

Date: Fri, 19 Dec 2003 03:12:57 +0900
From: Elias Athanasopoulos <[email protected]>
Newsgroups: comp.lang.ruby
Subject: Re: Yukihiro - Please ensure backwards compatibility

This is a deprecation warning. It will no longer be backwards compatible in
1.9 and later, IIRC (maybe as early as 1.8.1).

In 1.8.0, however, it's just a warning.

I had this "problem", too. I can't see why Ruby is so verbose on that
and doesn't interpret foo.gsub[!]("bar", ...) as foo.gsub[!](/bar/, ...)

automagically...

^^^^^^^^^^^^^
^^^^^^^^^^^^^

this word is the reason for many, many, many hours spent debugging perl
scripts. if you have done much perl programming you will know exactly what i
mean.

i'm all for backward compatibility - unless the 'old' way wasn't all that good.
IMHO, it wasn't all that good to be able to do this (same situation as gsub)


# why doesn't this work, after all my string does start with an 'a'?

~ > ruby16 -e 'puts( ("^a" =~ "ara") && "matched!" )'
nil


# oh right, wrong dang order - there went 10 minutes!

~ > ruby16 -e 'puts( ("ara" =~ "^a") && "matched!" )'
matched!



# now under ruby18 we are notified and have plenty of time to correct before
# 1.9. backward compat is also preserved.

~ > ruby18 -e 'puts( ("ara" =~ "^a") && "matched!" )'
-e:1: warning: string =~ string will be obsolete; use explicit regexp
matched!

~ > ruby18 -e 'puts( ("^a" =~ "ara") && "matched!" )'
-e:1: warning: string =~ string will be obsolete; use explicit regexp
nil


i'm all for this break of backward compat... my 2 cents.

-a
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[Florian Gross]

blah.gsub!("testing", ' ')
i got a message that it was going to ignore(?) this statement as
"testing" was not a regexp..... this hit me on more than one script,
forcing me into a quick-fix mode as i definitely was not anticipating
this script-debilitating "ignore" of my code...

Your statement won't be ignored, there will just be that warning. Why?
Because "...bar".gsub(".", "foo") produces "foofoofoobar" and not
"foofoofoofoofoofoo". This wasn't always this way -- in Ruby 1.6.8
Strings were handled just like Regexps in this case. I myself really
prefer the current behaviour to the old one because the old one is still
available (use /#{foo}/) and this allows you to easily substitute user
input without using the longish Regexp.escape() which would be forgotten
way to often and thus cause security risks anyway.

The warning will go away in 1.9.0, AFAIK. I'd suggest either using
/#{Regexp.escape(foo)}/ or disabling the warnings via the
-W0-command-line-option or $-w = nil for now.

Regards,
Florian Gross

 

[Martin DeMello]

I had this "problem", too. I can't see why Ruby is so verbose on that
and doesn't interpret foo.gsub[!]("bar", ...) as foo.gsub[!](/bar/, ...)
automagically...

Well, for one, I think more people would expect it to be interpreted as
foo.gsub(Regexp.quote(bar), ...)

martin

 

[Alexander Kellett]

I had this "problem", too. I can't see why Ruby is so verbose on that
and doesn't interpret foo.gsub[!]("bar", ...) as foo.gsub[!](/bar/, ...)
automagically...

Well, for one, I think more people would expect it to be interpreted as
foo.gsub(Regexp.quote(bar), ...)

/me nods
i use this same paradigm frequently.
its a bit icky for such a common action.

Alex

 

[Alexander Kellett]

I had this "problem", too. I can't see why Ruby is so verbose on that
and doesn't interpret foo.gsub[!]("bar", ...) as foo.gsub[!](/bar/, ...)
automagically...

Well, for one, I think more people would expect it to be interpreted as
foo.gsub(Regexp.quote(bar), ...)

/me nods
i use this same paradigm frequently.
its a bit icky for such a common action.

Alex

 

[John W. Long]

/me nods
i use this same paradigm frequently.
its a bit icky for such a common action.

how about:

foo.gsub!(/#{bar}/, ...)

fairly concise.

 

[Mauricio Fernández]

how about:

foo.gsub!(/#{bar}/, ...)

fairly concise.

=> nil

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-- Seen on #Debian

 

[James F. Hranicky]

I had this "problem", too. I can't see why Ruby is so verbose on that
and doesn't interpret foo.gsub[!]("bar", ...) as foo.gsub[!](/bar/, ...)
automagically...

The main reason I like this

line.match('/usr/local/lib/blah/blah/blah')

is so I don't have to escape forward slashes:

line.match(/\/usr\/local\/lib\/blah\/blah/)

I suppose writing this

line.match(Regexp.new("/usr/local/lib/blah/blah/blah"))

works, though a touch less elegant. No biggie, though. Perhaps there's a
better way than that?

Jim

 

[ts]

J> line.match(/\/usr\/local\/lib\/blah\/blah/)

svg% ruby -e 'p %r"/usr/local/lib/blah/blah/blah"'
/\/usr\/local\/lib\/blah\/blah\/blah/
svg%


Guy Decoux

 

[Jamis Buck]

The main reason I like this

line.match('/usr/local/lib/blah/blah/blah')

is so I don't have to escape forward slashes:

line.match(/\/usr\/local\/lib\/blah\/blah/)

I suppose writing this

line.match(Regexp.new("/usr/local/lib/blah/blah/blah"))

works, though a touch less elegant. No biggie, though. Perhaps there's a
better way than that?

Jim

You can use %r, and then specify your own delimiter:

line.match( %r|/usr/local/lib/blah/blah| )

 

[James F. Hranicky]

You can use %r, and then specify your own delimiter:

line.match( %r|/usr/local/lib/blah/blah| )

Works for me -- thanks, guys.

Jim