xref: /aosp_15_r20/external/libconfig/contrib/libconfig-ruby/README (revision 2e9d491483b805f09ea864149eadd5680efcc72a)

# << Usage >>

# you can feed this README to irb and see the result
# $ irb README

# IMPORTANT NOTICE:
# be careful with big *fixnum* (plain int) values in configs
# int is 32 bit, but ruby fixnum is only 31!
# For example, 2100000000 will be read as -47483648.

require 'rconfig'
c = Config.new

c.read!('test.cfg')
# => IOError
c.read('test.cfg')
# => false

p c['some_var']
# => SettingNotFoundError
# note: Config#lookup is alias for Config#[]

c.append 'fixnum', Config::Fixnum.new(150)
# #<Config::Fixnum...>

f1 = Config::Fixnum.new(1)
c.append 'another_fixnum', f1

f2 = Config::Fixnum.new(256)
c.append 'next_fixnum', f2

p c.size
# => 3

c.delete(f1)            # by element
c.delete(0)             # by index
c.delete('next_fixnum') # by name
# note: (at now) you cannot delete nested elements by Config#delete
#       you can do c['nested.element'].parent.delete(c['nested.element'])

p c.size
# => 0

l = Config::List.new
c.append 'the_list', l

l.append Config::String.new("abcdef")
l << Config::Float.new(3.14)
# note: Config::List#append and Config::Array#append both have
#       aliases Config::[Aggregate]#<<

p l.name
# => "the_list"

p l.index
# => 0

p l.root?
# => false

p l.size
# => 3

l[0].format = Config::FORMAT_HEX

p l[1].value
# => 3.14

l[1].value = 2.71828

c.write 'test.cfg'

# you will get test.cfg with following contents:
#
# the_list = ( "abcdef", 2.71828, 0x2A );
#