如果我想列出类的所有方法，我可以使用Class_Name.methods，例如，列出FixNum类中的所有方法：
> 5.methods
=> [:to_s, :-@, :+, :-, :*, :/, :div, :%, :modulo, :divmod, :fdiv, :**, :abs, :magnitude, :==, :===, :<=>, :>, :>=, :<, :<=, :~, :&, :|, :^, :[], :<<, :>>, :to_f, :size, :zero?, :odd?, :even?, :succ, :integer?, :upto, :downto, :times, :next, :pred, :chr, :ord, :to_i, :to_int, :floor, :ceil, :truncate, :round, :gcd, :lcm, :gcdlcm, :numerator, :denominator, :to_r, :rationalize, :singleton_method_added, :coerce, :i, :+@, :eql?, :quo, :remainder, :real?, :nonzero?, :step, :to_c, :real, :imaginary, :imag, :abs2, :arg, :angle, :phase, :rectangular, :rect, :polar, :conjugate, :conj, :between?, :nil?, :=~, :!~, :hash, :class, :singleton_class, :clone, :dup, :initialize_dup, :initialize_clone, :taint, :tainted?, :untaint, :untrust, :untrusted?, :trust, :freeze, :frozen?, :inspect, :methods, :singleton_methods, :protected_methods, :private_methods, :public_methods, :instance_variables, :instance_variable_get, :instance_variable_set, :instance_variable_defined?, :instance_of?, :kind_of?, :is_a?, :tap, :send, :public_send, :respond_to?, :respond_to_missing?, :extend, :display, :method, :public_method, :define_singleton_method, :object_id, :to_enum, :enum_for, :equal?, :!, :!=, :instance_eval, :instance_exec, :__send__, :__id__]
这个清单真的很难读。我也试过5.methods.sort，但这并没有让它更具可读性。
我经常在日常编程中使用方法列表。有没有办法漂亮地打印这个，所以它变得更容易阅读？
答案 0 :(得分：33)
试试这个单行：
puts 5.methods.sort
答案 1 :(得分：14)
我喜欢使用awesome_print。作为奖励，它为您提供彩色输出，方法和它们的来源：
1.9.3-p125 :001 > require 'ap'
=> true
1.9.3-p125 :002 > ap 5.methods; 0
[
[ 0] !() Fixnum (BasicObject)
[ 1] !=(arg1) Fixnum (BasicObject)
[ 2] !~(arg1) Fixnum (Kernel)
[ 3] %(arg1) Fixnum
[ 4] &(arg1) Fixnum
[ 5] *(arg1) Fixnum
[ 6] **(arg1) Fixnum
[ 7] +(arg1) Fixnum
[ 8] +@() Fixnum (Numeric)
[ 9] -(arg1) Fixnum
[ 10] -@() Fixnum
[ 11] /(arg1) Fixnum
[ 12] <(arg1) Fixnum
[ 13] <<(arg1) Fixnum
[ 14] <=(arg1) Fixnum
[ 15] <=>(arg1) Fixnum
[ 16] ==(arg1) Fixnum
[ 17] ===(arg1) Fixnum
[ 18] =~(arg1) Fixnum (Kernel)
[ 19] >(arg1) Fixnum
[ 20] >=(arg1) Fixnum
[ 21] >>(arg1) Fixnum
[ 22] [](arg1) Fixnum
[ 23] ^(arg1) Fixnum
[ 24] __id__() Fixnum (Kernel)
[ 25] __send__(*arg1) Fixnum (BasicObject)
[ 26] abs() Fixnum
[ 27] abs2() Fixnum (Numeric)
[ 28] ai(*options) Fixnum (Kernel)
[ 29] angle() Fixnum (Numeric)
[ 30] arg() Fixnum (Numeric)
[ 31] awesome_inspect(*options) Fixnum (Kernel)
[ 32] awesome_print(object, *options) Fixnum (Kernel)
[ 33] between?(arg1, arg2) Fixnum (Comparable)
[ 34] ceil() Fixnum (Integer)
[ 35] chr(*arg1) Fixnum (Integer)
[ 36] class() Fixnum (Kernel)
[ 37] clone() Fixnum (Kernel)
[ 38] coerce(arg1) Fixnum (Numeric)
[ 39] conj() Fixnum (Numeric)
[ 40] conjugate() Fixnum (Numeric)
[ 41] define_singleton_method(*arg1) Fixnum (Kernel)
[ 42] denominator() Fixnum (Integer)
[ 43] display(*arg1) Fixnum (Kernel)
[ 44] div(arg1) Fixnum
[ 45] divmod(arg1) Fixnum
[ 46] downto(arg1) Fixnum (Integer)
[ 47] dup() Fixnum (Kernel)
[ 48] enum_for(*arg1) Fixnum (Kernel)
[ 49] eql?(arg1) Fixnum (Numeric)
[ 50] equal?(arg1) Fixnum (BasicObject)
[ 51] even?() Fixnum
[ 52] extend(*arg1) Fixnum (Kernel)
[ 53] fdiv(arg1) Fixnum
[ 54] floor() Fixnum (Integer)
[ 55] freeze() Fixnum (Kernel)
[ 56] frozen?() Fixnum (Kernel)
[ 57] gcd(arg1) Fixnum (Integer)
[ 58] gcdlcm(arg1) Fixnum (Integer)
[ 59] hash() Fixnum (Kernel)
[ 60] i() Fixnum (Numeric)
[ 61] imag() Fixnum (Numeric)
[ 62] imaginary() Fixnum (Numeric)
[ 63] initialize_clone(arg1) Fixnum (Kernel)
[ 64] initialize_dup(arg1) Fixnum (Kernel)
[ 65] inspect() Fixnum (Kernel)
[ 66] instance_eval(*arg1) Fixnum (BasicObject)
[ 67] instance_exec(*arg1) Fixnum (BasicObject)
[ 68] instance_of?(arg1) Fixnum (Kernel)
[ 69] instance_variable_defined?(arg1) Fixnum (Kernel)
[ 70] instance_variable_get(arg1) Fixnum (Kernel)
[ 71] instance_variable_set(arg1, arg2) Fixnum (Kernel)
[ 72] instance_variables() Fixnum (Kernel)
[ 73] integer?() Fixnum (Integer)
[ 74] is_a?(arg1) Fixnum (Kernel)
[ 75] kind_of?(arg1) Fixnum (Kernel)
[ 76] lcm(arg1) Fixnum (Integer)
[ 77] magnitude() Fixnum
[ 78] method(arg1) Fixnum (Kernel)
[ 79] methods(*args) Fixnum (Object)
[ 80] modulo(arg1) Fixnum
[ 81] next() Fixnum (Integer)
[ 82] nil?() Fixnum (Kernel)
[ 83] nonzero?() Fixnum (Numeric)
[ 84] numerator() Fixnum (Integer)
[ 85] object_id() Fixnum (Kernel)
[ 86] odd?() Fixnum
[ 87] ord() Fixnum (Integer)
[ 88] phase() Fixnum (Numeric)
[ 89] polar() Fixnum (Numeric)
[ 90] pred() Fixnum (Integer)
[ 91] private_methods(*args) Fixnum (Object)
[ 92] protected_methods(*args) Fixnum (Object)
[ 93] public_method(arg1) Fixnum (Kernel)
[ 94] public_methods(*args) Fixnum (Object)
[ 95] public_send(*arg1) Fixnum (Kernel)
[ 96] quo(arg1) Fixnum (Numeric)
[ 97] rationalize(*arg1) Fixnum (Integer)
[ 98] real() Fixnum (Numeric)
[ 99] real?() Fixnum (Numeric)
[100] rect() Fixnum (Numeric)
[101] rectangular() Fixnum (Numeric)
[102] remainder(arg1) Fixnum (Numeric)
[103] respond_to?(*arg1) Fixnum (Kernel)
[104] respond_to_missing?(arg1, arg2) Fixnum (Kernel)
[105] round(*arg1) Fixnum (Integer)
[106] send(*arg1) Fixnum (Kernel)
[107] singleton_class() Fixnum (Kernel)
[108] singleton_method_added(arg1) Fixnum (Numeric)
[109] singleton_methods(*args) Fixnum (Object)
[110] size() Fixnum
[111] step(*arg1) Fixnum (Numeric)
[112] succ() Fixnum
[113] taint() Fixnum (Kernel)
[114] tainted?() Fixnum (Kernel)
[115] tap() Fixnum (Kernel)
[116] times() Fixnum (Integer)
[117] to_c() Fixnum (Numeric)
[118] to_enum(*arg1) Fixnum (Kernel)
[119] to_f() Fixnum
[120] to_i() Fixnum (Integer)
[121] to_int() Fixnum (Integer)
[122] to_r() Fixnum (Integer)
[123] to_s(*arg1) Fixnum
[124] truncate() Fixnum (Integer)
[125] trust() Fixnum (Kernel)
[126] untaint() Fixnum (Kernel)
[127] untrust() Fixnum (Kernel)
[128] untrusted?() Fixnum (Kernel)
[129] upto(arg1) Fixnum (Integer)
[130] zero?() Fixnum
[131] |(arg1) Fixnum
[132] ~() Fixnum
]
=> 0
答案 2 :(得分：5)
排除从Object继承的方法可能也很有用。
(Fixnum.public_instance_methods - Object.public_instance_methods).sort
=> [:%, :&, :*, :**, :+, :+@, :-, :-@, :/, :<, :<<, :<=, :>, :>=, :>>, :[], :^, :abs, :abs2, :angle, :arg, :between?, :ceil, :chr, :coerce, :conj, :conjugate, :denominator, :div, :divmod, :downto, :even?, :fdiv, :floor, :gcd, :gcdlcm, :i, :imag, :imaginary, :integer?, :lcm, :magnitude, :modulo, :next, :nonzero?, :numerator, :odd?, :ord, :phase, :polar, :pred, :quo, :rationalize, :real, :real?, :rect, :rectangular, :remainder, :round, :singleton_method_added, :size, :step, :succ, :times, :to_c, :to_f, :to_i, :to_int, :to_r, :truncate, :upto, :zero?, :|, :~]
或者更具可读性：
(Fixnum.public_instance_methods - Object.public_instance_methods).sort.join(" ")
=> "% & * ** + +@ - -@ / < << <= > >= >> [] ^ abs abs2 angle arg between? ceil chr coerce conj conjugate denominator div divmod downto even? fdiv floor gcd gcdlcm i imag imaginary integer? lcm magnitude modulo next nonzero? numerator odd? ord phase polar pred quo rationalize real real? rect rectangular remainder round singleton_method_added size step succ times to_c to_f to_i to_int to_r truncate upto zero? | ~"
答案 3 :(得分：4)
几乎开箱即用的简单方法是：
require 'yaml'
y (5.methods - Object.methods).sort
为方便起见，您还可以创建包含这些方法的.irbrc文件：
require 'yaml'
def yppo(obj)
y((obj.methods - Object.methods).sort)
end
def yppc(obj)
y((obj.methods - Class.methods).sort)
end
然后就像yppo(5)一样简单。
我通常使用的另一个技巧是grep方法：
y (5.methods - Object.methods).sort.grep /to_/
答案 4 :(得分：4)
事实上，你回答了自己的问题：
require 'pp'
pp 5.methods
[:to_s,
:-@,
:+,
:-,
:*,
:/,
:div,
:%,
:modulo,
:divmod,
:fdiv,
:**,
:abs,
:magnitude,
:==,
:===,
:<=>,
etc
答案 5 :(得分：0)
您好，这是一个简单的答案
5.methods.each {|x| p x}
现在解释。 ＆＃34; 5＆＃34;是＆＃34;数字＆＃34;并且可以是任何其他Interger ...... ＆＃34;。方法＆＃34;这将调用适用于数字的所有方法的列表...... ＆＃34; .each {| x | p x}＆＃34;这将在列表中打印所有方法。
我希望这会有所帮助。