Returns a Hash using named capture.
A key of the hash is a name of the named captures. A value of the hash is a string of last successful capture of corresponding group.
m = /(?<a>.)(?<b>.)/.match("01") m.named_captures #=> {"a" => "0", "b" => "1"} m = /(?<a>.)(?<b>.)?/.match("0") m.named_captures #=> {"a" => "0", "b" => nil} m = /(?<a>.)(?<a>.)/.match("01") m.named_captures #=> {"a" => "1"} m = /(?<a>x)|(?<a>y)/.match("x") m.named_captures #=> {"a" => "x"}
Returns the portion of the original string before the current match. Equivalent to the special variable $`.
m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.pre_match #=> "T"
Returns the group most recently added to the stack.
Contrived example:
out = ""
=> ""
q = PrettyPrint.new(out)
=> #<PrettyPrint:0x82f85c0 @output="", @maxwidth=79, @newline="\n", @genspace=#<Proc:0x82f8368@/home/vbatts/.rvm/rubies/ruby-head/lib/ruby/2.0.0/prettyprint.rb:82 (lambda)>, @output_width=0, @buffer_width=0, @buffer=[], @group_stack=[#<PrettyPrint::Group:0x82f8138 @depth=0, @breakables=[], @break=false>], @group_queue=#<PrettyPrint::GroupQueue:0x82fb7c0 @queue=[[#<PrettyPrint::Group:0x82f8138 @depth=0, @breakables=[], @break=false>]]>, @indent=0>
q.group {
q.text q.current_group.inspect
q.text q.newline
q.group(q.current_group.depth + 1) {
q.text q.current_group.inspect
q.text q.newline
q.group(q.current_group.depth + 1) {
q.text q.current_group.inspect
q.text q.newline
q.group(q.current_group.depth + 1) {
q.text q.current_group.inspect
q.text q.newline
}
}
}
}
=> 284
puts out
#<PrettyPrint::Group:0x8354758 @depth=1, @breakables=[], @break=false>
#<PrettyPrint::Group:0x8354550 @depth=2, @breakables=[], @break=false>
#<PrettyPrint::Group:0x83541cc @depth=3, @breakables=[], @break=false>
#<PrettyPrint::Group:0x8347e54 @depth=4, @breakables=[], @break=false>
This is similar to breakable except the decision to break or not is determined individually.
Two fill_breakable under a group may cause 4 results: (break,break), (break,non-break), (non-break,break), (non-break,non-break). This is different to breakable because two breakable under a group may cause 2 results: (break,break), (non-break,non-break).
The text sep is inserted if a line is not broken at this point.
If sep is not specified, “ ” is used.
If width is not specified, sep.length is used. You will have to specify this when sep is a multibyte character, for example.
Iterates over all IP addresses for name.
Iterates over all IP addresses for name.
Returns an array of the names of the thread-local variables (as Symbols).
thr = Thread.new do Thread.current.thread_variable_set(:cat, 'meow') Thread.current.thread_variable_set("dog", 'woof') end thr.join #=> #<Thread:0x401b3f10 dead> thr.thread_variables #=> [:dog, :cat]
Note that these are not fiber local variables. Please see Thread#[] and Thread#thread_variable_get for more details.
Returns true if the given string (or symbol) exists as a thread-local variable.
me = Thread.current me.thread_variable_set(:oliver, "a") me.thread_variable?(:oliver) #=> true me.thread_variable?(:stanley) #=> false
Note that these are not fiber local variables. Please see Thread#[] and Thread#thread_variable_get for more details.
Returns the safe level in effect for thr. Setting thread-local safe levels can help when implementing sandboxes which run insecure code.
thr = Thread.new { $SAFE = 1; sleep } Thread.current.safe_level #=> 0 thr.safe_level #=> 1
Return value from :return, c_return, and b_return event
Returns true if yield would execute a block in the current context. The iterator? form is mildly deprecated.
def try if block_given? yield else "no block" end end try #=> "no block" try { "hello" } #=> "hello" try do "hello" end #=> "hello"
Creates an enumerator for each chunked elements. The beginnings of chunks are defined by pattern and the block.
If pattern === elt returns true or the block returns true for the element, the element is beginning of a chunk.
The === and block is called from the first element to the last element of enum. The result for the first element is ignored.
The result enumerator yields the chunked elements as an array. So each method can be called as follows:
enum.slice_before(pattern).each { |ary| ... }
enum.slice_before { |elt| bool }.each { |ary| ... }
Other methods of the Enumerator class and Enumerable module, such as to_a, map, etc., are also usable.
For example, iteration over ChangeLog entries can be implemented as follows:
# iterate over ChangeLog entries. open("ChangeLog") { |f| f.slice_before(/\A\S/).each { |e| pp e } } # same as above. block is used instead of pattern argument. open("ChangeLog") { |f| f.slice_before { |line| /\A\S/ === line }.each { |e| pp e } }
“svn proplist -R” produces multiline output for each file. They can be chunked as follows:
IO.popen([{"LC_ALL"=>"C"}, "svn", "proplist", "-R"]) { |f| f.lines.slice_before(/\AProp/).each { |lines| p lines } } #=> ["Properties on '.':\n", " svn:ignore\n", " svk:merge\n"] # ["Properties on 'goruby.c':\n", " svn:eol-style\n"] # ["Properties on 'complex.c':\n", " svn:mime-type\n", " svn:eol-style\n"] # ["Properties on 'regparse.c':\n", " svn:eol-style\n"] # ...
If the block needs to maintain state over multiple elements, local variables can be used. For example, three or more consecutive increasing numbers can be squashed as follows (see chunk_while for a better way):
a = [0, 2, 3, 4, 6, 7, 9] prev = a[0] p a.slice_before { |e| prev, prev2 = e, prev prev2 + 1 != e }.map { |es| es.length <= 2 ? es.join(",") : "#{es.first}-#{es.last}" }.join(",") #=> "0,2-4,6,7,9"
However local variables should be used carefully if the result enumerator is enumerated twice or more. The local variables should be initialized for each enumeration. Enumerator.new can be used to do it.
# Word wrapping. This assumes all characters have same width. def wordwrap(words, maxwidth) Enumerator.new {|y| # cols is initialized in Enumerator.new. cols = 0 words.slice_before { |w| cols += 1 if cols != 0 cols += w.length if maxwidth < cols cols = w.length true else false end }.each {|ws| y.yield ws } } end text = (1..20).to_a.join(" ") enum = wordwrap(text.split(/\s+/), 10) puts "-"*10 enum.each { |ws| puts ws.join(" ") } # first enumeration. puts "-"*10 enum.each { |ws| puts ws.join(" ") } # second enumeration generates same result as the first. puts "-"*10 #=> ---------- # 1 2 3 4 5 # 6 7 8 9 10 # 11 12 13 # 14 15 16 # 17 18 19 # 20 # ---------- # 1 2 3 4 5 # 6 7 8 9 10 # 11 12 13 # 14 15 16 # 17 18 19 # 20 # ----------
mbox contains series of mails which start with Unix From line. So each mail can be extracted by slice before Unix From line.
# parse mbox open("mbox") { |f| f.slice_before { |line| line.start_with? "From " }.each { |mail| unix_from = mail.shift i = mail.index("\n") header = mail[0...i] body = mail[(i+1)..-1] body.pop if body.last == "\n" fields = header.slice_before { |line| !" \t".include?(line[0]) }.to_a p unix_from pp fields pp body } } # split mails in mbox (slice before Unix From line after an empty line) open("mbox") { |f| emp = true f.slice_before { |line| prevemp = emp emp = line == "\n" prevemp && line.start_with?("From ") }.each { |mail| mail.pop if mail.last == "\n" pp mail } }
Returns a hash that contains filename as key and coverage array as value.
Generate a JSON document from the Ruby data structure obj and return it. The returned document is a prettier form of the document returned by unparse.
The opts argument can be used to configure the generator. See the generate method for a more detailed explanation.
Recursively calls passed Proc if the parsed data structure is an Array or Hash
Return consuming memory size of obj.
Note that the return size is incomplete. You need to deal with this information as only a HINT. Especially, the size of T_DATA may not be correct.
This method is only expected to work with C Ruby.
From Ruby 2.2, memsize_of(obj) returns a memory size includes sizeof(RVALUE).
Turns FIPS mode on or off. Turning on FIPS mode will obviously only have an effect for FIPS-capable installations of the OpenSSL library. Trying to do so otherwise will result in an error.
OpenSSL.fips_mode = true # turn FIPS mode on OpenSSL.fips_mode = false # and off again