Returns an Array of method names which have any options.
p FileUtils.commands #=> ["chmod", "cp", "cp_r", "install", ...]
Get the default RubyGems API host. This is normally https://rubygems.org.
Set the default RubyGems API host.
Raises a TypeError to prevent cloning.
Computes the cosine of x (expressed in radians). Returns a Float in the range -1.0..1.0.
Domain: (-INFINITY, INFINITY)
Codomain: [-1, 1]
Math.cos(Math::PI) #=> -1.0
Computes the arc cosine of x. Returns 0..PI.
Domain: [-1, 1]
Codomain: [0, PI]
Math.acos(0) == Math::PI/2 #=> true
Computes the hyperbolic cosine of x (expressed in radians).
Domain: (-INFINITY, INFINITY)
Codomain: [1, INFINITY)
Math.cosh(0) #=> 1.0
Computes the inverse hyperbolic cosine of x.
Domain: [1, INFINITY)
Codomain: [0, INFINITY)
Math.acosh(1) #=> 0.0
Returns a list of signal names mapped to the corresponding underlying signal numbers.
Signal.list #=> {"EXIT"=>0, "HUP"=>1, "INT"=>2, "QUIT"=>3, "ILL"=>4, "TRAP"=>5, "IOT"=>6, "ABRT"=>6, "FPE"=>8, "KILL"=>9, "BUS"=>7, "SEGV"=>11, "SYS"=>31, "PIPE"=>13, "ALRM"=>14, "TERM"=>15, "URG"=>23, "STOP"=>19, "TSTP"=>20, "CONT"=>18, "CHLD"=>17, "CLD"=>17, "TTIN"=>21, "TTOU"=>22, "IO"=>29, "XCPU"=>24, "XFSZ"=>25, "VTALRM"=>26, "PROF"=>27, "WINCH"=>28, "USR1"=>10, "USR2"=>12, "PWR"=>30, "POLL"=>29}