Feature #15231
Remove `Object#=~`
Description
Object#=~
receives (and just discards) an argument, and always returns nil. What purpose is this method for?
The following behavior that Object#=~
caused was confusing to me.
["foo"] =~ /foo/ #=> nil
More precisely: the actual example that I encountered was to parse coverage data from output of coverage measurement tool by using Open3.capture2
:
out = Open3.capture2("gcov", ...) # BUG: `out, =` was intended
if out =~ /lines\.*: *(\d+\.\d+)%/
...
end
Obviously, I forgot a comma to receive the return value of Open3.capture2
. The method returns a two-element array, and out =~
calls Object#=~
, which hid the bug. (Worse, I took several tens of minutes to debug it because I first thought that this is a bug of regexp, and spent tweaking the regexp.)
I guess Object#=~
was intended for general pattern matching, but presently the role was taken over by Object#===
.
So. How about removing Object#=~
?
Concerns:
- usa (Usaku NAKAMURA) said
NilClass#=~
should be newly introduced because of:if gets =~ /re/
Object#!~
is difficult to remove: some classes define only#=~
, and expectObject#!~
to delegate to#=~
.
Associated revisions
lib/webrick: explicitly convert header values to a string
The values of @header are expected to be all strings;
WEBrick::HTTPResponse::[]=(key, val) explicitly converts the second
argument to a string and assigns it to @header hash.
However, there were some points in WEBrick internal code that assigns
non-String to @header. This change fixes the issues.
The values are checked by header_value =~ /\r\n/
in check_header.
The type confusion caused conflict with removal of Object#=~
[Feature #15231].
lib/webrick: explicitly convert header values to a string
The values of @header are expected to be all strings;
WEBrick::HTTPResponse::[]=(key, val) explicitly converts the second
argument to a string and assigns it to @header hash.
However, there were some points in WEBrick internal code that assigns
non-String to @header. This change fixes the issues.
The values are checked by header_value =~ /\r\n/
in check_header.
The type confusion caused conflict with removal of Object#=~
[Feature #15231].
lib/rdoc/markup/: Remove wrong call to =~
against Array
@res
is an Array, so @res =~ /\n\z/
calls Object#=~
which always
returns nil.
I guess it should be @res.last =~ /\n\z/
, but the change causes test
failures.
This bug was found during work for removal of Object#=~
.
[Feature #15231]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65985 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
lib/rdoc/markup/: Remove wrong call to =~
against Array
@res
is an Array, so @res =~ /\n\z/
calls Object#=~
which always
returns nil.
I guess it should be @res.last =~ /\n\z/
, but the change causes test
failures.
This bug was found during work for removal of Object#=~
.
[Feature #15231]
lib/rdoc/markup/: Remove wrong call to =~
against Array
@res
is an Array, so @res =~ /\n\z/
calls Object#=~
which always
returns nil.
I guess it should be @res.last =~ /\n\z/
, but the change causes test
failures.
This bug was found during work for removal of Object#=~
.
[Feature #15231]
test/rdoc/test_rdoc_rdoc.rb: add dummy finish
RDoc::Options#@exclude is initialized as an empty array.
Then, #finish converts it to a regexp or nil and reassign it to @exclude.
Some methods of RDoc assumes that #finish has been already called.
So, this change forces to assign nil to @exclude.
This type confusion was found during work for removal of Object#=~
.
[Feature #15231]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65986 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
test/rdoc/test_rdoc_rdoc.rb: add dummy finish
RDoc::Options#@exclude is initialized as an empty array.
Then, #finish converts it to a regexp or nil and reassign it to @exclude.
Some methods of RDoc assumes that #finish has been already called.
So, this change forces to assign nil to @exclude.
This type confusion was found during work for removal of Object#=~
.
[Feature #15231]
test/rdoc/test_rdoc_rdoc.rb: add dummy finish
RDoc::Options#@exclude is initialized as an empty array.
Then, #finish converts it to a regexp or nil and reassign it to @exclude.
Some methods of RDoc assumes that #finish has been already called.
So, this change forces to assign nil to @exclude.
This type confusion was found during work for removal of Object#=~
.
[Feature #15231]
lib/rubygems: explicitly clarify the type for =~ matching
RubyGems is very indifferent for type.
This change is needed for removal of Object#=~
. [Feature #15231]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65988 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
lib/rubygems: explicitly clarify the type for =~ matching
RubyGems is very indifferent for type.
This change is needed for removal of Object#=~
. [Feature #15231]
lib/rubygems: explicitly clarify the type for =~ matching
RubyGems is very indifferent for type.
This change is needed for removal of Object#=~
. [Feature #15231]
object.c: Deprecate Object#=~ and add NilClass#=~`
Object#=~ always returns nil. This behavior is not only unuseful but
also troublesome because it may hide a type error.
This change deprecates Object#=~. For compatibility, NilClass#=~ is
newly introduced. [Feature #15231]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65989 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
object.c: Deprecate Object#=~ and add NilClass#=~`
Object#=~ always returns nil. This behavior is not only unuseful but
also troublesome because it may hide a type error.
This change deprecates Object#=~. For compatibility, NilClass#=~ is
newly introduced. [Feature #15231]
object.c: Deprecate Object#=~ and add NilClass#=~`
Object#=~ always returns nil. This behavior is not only unuseful but
also troublesome because it may hide a type error.
This change deprecates Object#=~. For compatibility, NilClass#=~ is
newly introduced. [Feature #15231]
Show the class of the receiver [Feature #15231]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66261 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Show the class of the receiver [Feature #15231]
Show the class of the receiver [Feature #15231]
History
Updated by naruse (Yui NARUSE) about 1 year ago
rubocop should alert obj =~ re
to fix as re =~ obj
.
Updated by sawa (Tsuyoshi Sawada) about 1 year ago
I agree. At the same time, the String=~
behaviour:
str =~ obj → integer or nil click to toggle source
Match—If obj is a Regexp, use it as a pattern to match against str,and returns the position the match starts, or nil if there is no match. Otherwise, invokes obj.=~, passing str as an argument. The default =~ in Object returns nil.
(from https://ruby-doc.org/core-2.4.0/String.html#method-i-3D~)
should be changed to raise a TypeError
when obj
is not a Regexp
, on a par with Regexp#=~
given a non-String
argument. Afterall, the following unnatural asymmetry in the current behaviour should be resolved:
// =~ Object.new # >> TypeError: no implicit conversion of Object into String
"" =~ Object.new # => nil
Updated by znz (Kazuhiro NISHIYAMA) about 1 year ago
"" =~ "" #=> TypeError (type mismatch: String given)
Updated by matz (Yukihiro Matsumoto) about 1 year ago
I vote for the proposed change. Let's give deprecation warning first. I don't think we need to remove !~
from Kernel
.
Matz.
Updated by mame (Yusuke Endoh) about 1 year ago
- Status changed from Open to Closed
Applied in changeset trunk|r65984.
lib/webrick: explicitly convert header values to a string
The values of @header are expected to be all strings;
WEBrick::HTTPResponse::[]=(key, val) explicitly converts the second
argument to a string and assigns it to @header hash.
However, there were some points in WEBrick internal code that assigns
non-String to @header. This change fixes the issues.
The values are checked by header_value =~ /\r\n/
in check_header.
The type confusion caused conflict with removal of Object#=~
[Feature #15231].
lib/webrick: explicitly convert header values to a string
The values of @header are expected to be all strings;
WEBrick::HTTPResponse::[]=(key, val) explicitly converts the second
argument to a string and assigns it to @header hash.
However, there were some points in WEBrick internal code that assigns
non-String to @header. This change fixes the issues.
The values are checked by
header_value =~ /\r\n/
in check_header.The type confusion caused conflict with removal of
Object#=~
[Feature #15231].
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65984 b2dd03c8-39d4-4d8f-98ff-823fe69b080e