Adds the contents of other_hash to hsh. If no block is specified, entries with duplicate keys are overwritten with the values from other_hash, otherwise the value of each duplicate key is determined by calling the block with the key, its value in hsh and its value in other_hash.
h1 = { "a" => 100, "b" => 200 } h2 = { "b" => 254, "c" => 300 } h1.merge!(h2) #=> {"a"=>100, "b"=>254, "c"=>300} h1 #=> {"a"=>100, "b"=>254, "c"=>300} h1 = { "a" => 100, "b" => 200 } h2 = { "b" => 254, "c" => 300 } h1.merge!(h2) { |key, v1, v2| v1 } #=> {"a"=>100, "b"=>200, "c"=>300} h1 #=> {"a"=>100, "b"=>200, "c"=>300}
Adds the contents of other_hash to hsh. If no block is specified, entries with duplicate keys are overwritten with the values from other_hash, otherwise the value of each duplicate key is determined by calling the block with the key, its value in hsh and its value in other_hash.
h1 = { "a" => 100, "b" => 200 } h2 = { "b" => 254, "c" => 300 } h1.merge!(h2) #=> {"a"=>100, "b"=>254, "c"=>300} h1 #=> {"a"=>100, "b"=>254, "c"=>300} h1 = { "a" => 100, "b" => 200 } h2 = { "b" => 254, "c" => 300 } h1.merge!(h2) { |key, v1, v2| v1 } #=> {"a"=>100, "b"=>200, "c"=>300} h1 #=> {"a"=>100, "b"=>200, "c"=>300}
Returns a new hash containing the contents of other_hash and the contents of hsh. If no block is specified, the value for entries with duplicate keys will be that of other_hash. Otherwise the value for each duplicate key is determined by calling the block with the key, its value in hsh and its value in other_hash.
h1 = { "a" => 100, "b" => 200 } h2 = { "b" => 254, "c" => 300 } h1.merge(h2) #=> {"a"=>100, "b"=>254, "c"=>300} h1.merge(h2){|key, oldval, newval| newval - oldval} #=> {"a"=>100, "b"=>54, "c"=>300} h1 #=> {"a"=>100, "b"=>200}
Returns a new array that is a one-dimensional flattening of this hash. That is, for every key or value that is an array, extract its elements into the new array. Unlike Array#flatten, this method does not flatten recursively by default. The optional level argument determines the level of recursion to flatten.
a = {1=> "one", 2 => [2,"two"], 3 => "three"} a.flatten # => [1, "one", 2, [2, "two"], 3, "three"] a.flatten(2) # => [1, "one", 2, 2, "two", 3, "three"]
Returns a new hash with the nil values/key pairs removed
h = { a: 1, b: false, c: nil } h.compact #=> { a: 1, b: false } h #=> { a: 1, b: false, c: nil }
Removes all nil values from the hash. Returns nil if no changes were made, otherwise returns the hash.
h = { a: 1, b: false, c: nil } h.compact! #=> { a: 1, b: false }
Returns true if the given key is present in hsh.
h = { "a" => 100, "b" => 200 } h.has_key?("a") #=> true h.has_key?("z") #=> false
Note that include? and member? do not test member equality using == as do other Enumerables.
See also Enumerable#include?
Adds the contents of hash to the environment variables. If no block is specified entries with duplicate keys are overwritten, otherwise the value of each duplicate name is determined by calling the block with the key, its value from the environment and its value from the hash.
Returns the number of environment variables.
Returns true if there is an environment variable with the given name.
Reads at most maxlen bytes from the ARGF stream.
If the optional outbuf argument is present, it must reference a String, which will receive the data. The outbuf will contain only the received data after the method call even if it is not empty at the beginning.
It raises EOFError on end of ARGF stream. Since ARGF stream is a concatenation of multiple files, internally EOF is occur for each file. ARGF.readpartial returns empty strings for EOFs except the last one and raises EOFError for the last one.
Returns a Hash containing implementation-dependent counters inside the VM.
This hash includes information about method/constant cache serials:
{
:global_method_state=>251,
:global_constant_state=>481,
:class_serial=>9029
}
The contents of the hash are implementation specific and may be changed in the future.
This method is only expected to work on C Ruby.
Parse an HTTP query string into a hash of key=>value pairs.
params = CGI::parse("query_string") # {"name1" => ["value1", "value2", ...], # "name2" => ["value1", "value2", ...], ... }
This method wraps a String you provide, or an empty default String, in a CSV object which is passed to the provided block. You can use the block to append CSV rows to the String and when the block exits, the final String will be returned.
Note that a passed String is modified by this method. Call dup() before passing if you need a new String.
The options parameter can be anything CSV::new() understands. This method understands an additional :encoding parameter when not passed a String to set the base Encoding for the output. CSV needs this hint if you plan to output non-ASCII compatible data.
This method can be used to easily parse CSV out of a String. You may either provide a block which will be called with each row of the String in turn, or just use the returned Array of Arrays (when no block is given).
You pass your str to read from, and an optional options containing anything CSV::new() understands.
Returns true if the ipaddr is a private address. IPv4 addresses in 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16 as defined in RFC 1918 and IPv6 Unique Local Addresses in fc00::/7 as defined in RFC 4193 are considered private.
Returns true iff the current severity level allows for the printing of FATAL messages.
Creates a matrix where the diagonal elements are composed of values.
Matrix.diagonal(9, 5, -3)
=> 9 0 0
0 5 0
0 0 -3
Returns true if this is a diagonal matrix. Raises an error if matrix is not square.
Returns true if this is a permutation matrix Raises an error if matrix is not square.