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instance method

Random::Formatter#hex

hex(n=nil)

# File tmp/rubies/ruby-3.0.5/lib/securerandom.rb, line 158
def hex(n=nil)
  random_bytes(n).unpack("H*")[0]
end

SecureRandom.hex generates a random hexadecimal string.

The argument n specifies the length, in bytes, of the random number to be generated. The length of the resulting hexadecimal string is twice of n.

If n is not specified or is nil, 16 is assumed. It may be larger in the future.

The result may contain 0-9 and a-f.

Example

require 'securerandom'

SecureRandom.hex #=> "eb693ec8252cd630102fd0d0fb7c3485"
SecureRandom.hex #=> "91dc3bfb4de5b11d029d376634589b61"

If a secure random number generator is not available, NotImplementedError is raised.

See also #gen_random #rand #choose #random_bytes also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.1