Try to convert obj into a hash, using to_hash method. Returns converted hash or nil if obj cannot be converted for any reason.
Hash.try_convert({1=>2}) # => {1=>2} Hash.try_convert("1=>2") # => nil
Replaces the contents of hsh with the contents of other_hash.
h = { "a" => 100, "b" => 200 } h.replace({ "c" => 300, "d" => 400 }) #=> {"c"=>300, "d"=>400}
Returns a new hash with the results of running the block once for every key. This method does not change the values.
h = { a: 1, b: 2, c: 3 } h.transform_keys {|k| k.to_s } #=> { "a" => 1, "b" => 2, "c" => 3 } h.transform_keys(&:to_s) #=> { "a" => 1, "b" => 2, "c" => 3 } h.transform_keys.with_index {|k, i| "#{k}.#{i}" } #=> { "a.0" => 1, "b.1" => 2, "c.2" => 3 }
If no block is given, an enumerator is returned instead.
Invokes the given block once for each key in hsh, replacing it with the new key returned by the block, and then returns hsh. This method does not change the values.
h = { a: 1, b: 2, c: 3 } h.transform_keys! {|k| k.to_s } #=> { "a" => 1, "b" => 2, "c" => 3 } h.transform_keys!(&:to_sym) #=> { a: 1, b: 2, c: 3 } h.transform_keys!.with_index {|k, i| "#{k}.#{i}" } #=> { "a.0" => 1, "b.1" => 2, "c.2" => 3 }
If no block is given, an enumerator is returned instead.
Returns a new hash with the results of running the block once for every value. This method does not change the keys.
h = { a: 1, b: 2, c: 3 } h.transform_values {|v| v * v + 1 } #=> { a: 2, b: 5, c: 10 } h.transform_values(&:to_s) #=> { a: "1", b: "2", c: "3" } h.transform_values.with_index {|v, i| "#{v}.#{i}" } #=> { a: "1.0", b: "2.1", c: "3.2" }
If no block is given, an enumerator is returned instead.
Invokes the given block once for each value in hsh, replacing it with the new value returned by the block, and then returns hsh. This method does not change the keys.
h = { a: 1, b: 2, c: 3 } h.transform_values! {|v| v * v + 1 } #=> { a: 2, b: 5, c: 10 } h.transform_values!(&:to_s) #=> { a: "2", b: "5", c: "10" } h.transform_values!.with_index {|v, i| "#{v}.#{i}" } #=> { a: "2.0", b: "5.1", c: "10.2" }
If no block is given, an enumerator is returned instead.
Returns an enumerator which iterates over each line (separated by sep, which defaults to your platform’s newline character) of each file in ARGV. If a block is supplied, each line in turn will be yielded to the block, otherwise an enumerator is returned. The optional limit argument is an Integer specifying the maximum length of each line; longer lines will be split according to this limit.
This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last line of the first file has been returned, the first line of the second file is returned. The ARGF.filename and ARGF.lineno methods can be used to determine the filename of the current line and line number of the whole input, respectively.
For example, the following code prints out each line of each named file prefixed with its line number, displaying the filename once per file:
ARGF.each_line do |line| puts ARGF.filename if ARGF.file.lineno == 1 puts "#{ARGF.file.lineno}: #{line}" end
While the following code prints only the first file’s name at first, and the contents with line number counted through all named files.
ARGF.each_line do |line| puts ARGF.filename if ARGF.lineno == 1 puts "#{ARGF.lineno}: #{line}" end
Iterates over each codepoint of each file in ARGF.
This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last codepoint of the first file has been returned, the first codepoint of the second file is returned. The ARGF.filename method can be used to determine the name of the file in which the current codepoint appears.
If no block is given, an enumerator is returned instead.
Returns the file extension appended to the names of modified files under in-place edit mode. This value can be set using ARGF.inplace_mode= or passing the -i switch to the Ruby binary.
Sets the filename extension for in-place editing mode to the given String. Each file being edited has this value appended to its filename. The modified file is saved under this new name.
For example:
$ ruby argf.rb file.txt
ARGF.inplace_mode = '.bak'
ARGF.each_line do |line|
print line.sub("foo","bar")
end
Each line of file.txt has the first occurrence of “foo” replaced with “bar”, then the new line is written out to file.txt.bak.
This method is a shortcut for converting a single row (Array) into a CSV String.
The options parameter can be anything CSV::new() understands. This method understands an additional :encoding parameter to set the base Encoding for the output. This method will try to guess your Encoding from the first non-nil field in row, if possible, but you may need to use this parameter as a backup plan.
The :row_sep option defaults to $INPUT_RECORD_SEPARATOR ($/) when calling this method.
This method is a shortcut for converting a single line of a CSV String into an Array. Note that if line contains multiple rows, anything beyond the first row is ignored.
The options parameter can be anything CSV::new() understands.
The regex marking a line as a comment. See CSV::new for details.
Returns true if headers are written in output. See CSV::new for details.
Returns the list of break points where execution will be stopped.
See DEBUGGER__ for more usage
Returns true if the ipaddr is a link-local address. IPv4 addresses in 169.254.0.0/16 reserved by RFC 3927 and Link-Local IPv6 Unicast Addresses in fe80::/10 reserved by RFC 4291 are considered link-local.
Returns a string for DNS reverse lookup compatible with RFC1886.
Creates a Range object for the network address.
Returns the names of the binding’s local variables as symbols.
def foo a = 1 2.times do |n| binding.local_variables #=> [:a, :n] end end
This method is the short version of the following code:
binding.eval("local_variables")