Results for: "Dir.chdir"

Calls the block once for each key string in the database. Returns self.

Executes the block for every line in ios, where lines are separated by sep. ios must be opened for reading or an IOError will be raised.

If no block is given, an enumerator is returned instead.

f = File.new("testfile")
f.each {|line| puts "#{f.lineno}: #{line}" }

produces:

1: This is line one
2: This is line two
3: This is line three
4: And so on...

See IO.readlines for details about getline_args.

Calls the given block once for each byte (0..255) in ios, passing the byte as an argument. The stream must be opened for reading or an IOError will be raised.

If no block is given, an enumerator is returned instead.

f = File.new("testfile")
checksum = 0
f.each_byte {|x| checksum ^= x }   #=> #<File:testfile>
checksum                           #=> 12

Passes the Integer ordinal of each character in ios, passing the codepoint as an argument. The stream must be opened for reading or an IOError will be raised.

If no block is given, an enumerator is returned instead.

Executes block for each key in the database, passing the corresponding value as a parameter.

Executes block for each key in the database, passing the key as a parameter.

The first form returns the MatchData object generated by the last successful pattern match. Equivalent to reading the special global variable $~ (see Special global variables in Regexp for details).

The second form returns the nth field in this MatchData object. n can be a string or symbol to reference a named capture.

Note that the last_match is local to the thread and method scope of the method that did the pattern match.

/c(.)t/ =~ 'cat'        #=> 0
Regexp.last_match       #=> #<MatchData "cat" 1:"a">
Regexp.last_match(0)    #=> "cat"
Regexp.last_match(1)    #=> "a"
Regexp.last_match(2)    #=> nil

/(?<lhs>\w+)\s*=\s*(?<rhs>\w+)/ =~ "var = val"
Regexp.last_match       #=> #<MatchData "var = val" lhs:"var" rhs:"val">
Regexp.last_match(:lhs) #=> "var"
Regexp.last_match(:rhs) #=> "val"

Iterates over each component of the path.

Pathname.new("/usr/bin/ruby").each_filename {|filename| ... }
  # yields "usr", "bin", and "ruby".

Returns an Enumerator if no block was given.

enum = Pathname.new("/usr/bin/ruby").each_filename
  # ... do stuff ...
enum.each { |e| ... }
  # yields "usr", "bin", and "ruby".

Iterates over each line in the file and yields a String object for each.

Iterates over the entries (files and subdirectories) in the directory, yielding a Pathname object for each entry.

Iterates over each value in the database.

If no block is given, returns an Enumerator.

Iterates over each key in the database.

If no block is given, returns an Enumerator.

See IO#each.

See IO#each_byte.

See IO#each_codepoint.

This returns the value that scan_until would return, without advancing the scan pointer. The match register is affected, though.

s = StringScanner.new("Fri Dec 12 1975 14:39")
s.check_until /12/          # -> "Fri Dec 12"
s.pos                       # -> 0
s.matched                   # -> 12

Mnemonic: it “checks” to see whether a scan_until will return a value.

Scans the string until the pattern is matched. Advances the scan pointer if advance_pointer_p, otherwise not. Returns the matched string if return_string_p is true, otherwise returns the number of bytes advanced. This method does affect the match register.

Returns the size of the most recent match (see matched), or nil if there was no recent match.

s = StringScanner.new('test string')
s.check /\w+/           # -> "test"
s.matched_size          # -> 4
s.check /\d+/           # -> nil
s.matched_size          # -> nil

Returns the pre-match

s = StringScanner.new('test string')
s.scan(/\w+/)           # -> "test"
s.scan(/\s+/)           # -> " "
s.pre_match             # -> "test"
s.post_match            # -> "string"

Returns the post-match

s = StringScanner.new('test string')
s.scan(/\w+/)           # -> "test"
s.scan(/\s+/)           # -> " "
s.pre_match             # -> "test"
s.post_match            # -> "string"

Calls block once for each key in hsh, passing the value as a parameter.

If no block is given, an enumerator is returned instead.

h = { "a" => 100, "b" => 200 }
h.each_value {|value| puts value }

produces:

100
200

Calls block once for each key in hsh, passing the key as a parameter.

If no block is given, an enumerator is returned instead.

h = { "a" => 100, "b" => 200 }
h.each_key {|key| puts key }

produces:

a
b

Returns an array containing the values associated with the given keys but also raises KeyError when one of keys can’t be found. Also see Hash#values_at and Hash#fetch.

h = { "cat" => "feline", "dog" => "canine", "cow" => "bovine" }

h.fetch_values("cow", "cat")                   #=> ["bovine", "feline"]
h.fetch_values("cow", "bird")                  # raises KeyError
h.fetch_values("cow", "bird") { |k| k.upcase } #=> ["bovine", "BIRD"]

Yields each environment variable name.

An Enumerator is returned if no block is given.

Yields each environment variable value.

An Enumerator is returned if no block was given.