In the first form, returns an array of the names of all constants accessible from the point of call. This list includes the names of all modules and classes defined in the global scope.
Module.constants.first(4) # => [:ARGF, :ARGV, :ArgumentError, :Array] Module.constants.include?(:SEEK_SET) # => false class IO Module.constants.include?(:SEEK_SET) # => true end
The second form calls the instance method constants.
Returns a list of modules included/prepended in mod (including mod itself).
module Mod include Math include Comparable prepend Enumerable end Mod.ancestors #=> [Enumerable, Mod, Comparable, Math] Math.ancestors #=> [Math] Enumerable.ancestors #=> [Enumerable]
Returns an array of the names of the constants accessible in mod. This includes the names of constants in any included modules (example at start of section), unless the inherit parameter is set to false.
The implementation makes no guarantees about the order in which the constants are yielded.
IO.constants.include?(:SYNC) #=> true IO.constants(false).include?(:SYNC) #=> false
Also see Module::const_defined?.
Returns the BigDecimal version number.
Returns the remainder from dividing by the value.
x.remainder(y) means x-y*(x/y).truncate
Returns the value raised to the power of n.
Note that n must be an Integer.
Also available as the operator **.
Returns True if the value is zero.
The coerce method provides support for Ruby type coercion. It is not enabled by default.
This means that binary operations like + * / or - can often be performed on a BigDecimal and an object of another type, if the other object can be coerced into a BigDecimal value.
e.g.
a = BigDecimal.new("1.0") b = a / 2.0 #=> 0.5
Note that coercing a String to a BigDecimal is not supported by default; it requires a special compile-time option when building Ruby.
Returns the exponent of the BigDecimal number, as an Integer.
If the number can be represented as 0.xxxxxx*10**n where xxxxxx is a string of digits with no leading zeros, then n is the exponent.
Since int is already an Integer, this always returns true.
Iterates the given block, passing in integer values from int up to and including limit.
If no block is given, an Enumerator is returned instead.
For example:
5.upto(10) { |i| print i, " " } #=> 5 6 7 8 9 10
Iterates the given block int times, passing in values from zero to int - 1.
If no block is given, an Enumerator is returned instead.
5.times do |i| print i, " " end #=> 0 1 2 3 4
Returns self.
Returns the numerator.
Rational(7).numerator #=> 7 Rational(7, 1).numerator #=> 7 Rational(9, -4).numerator #=> -9 Rational(-2, -10).numerator #=> 1
Creates a date object denoting the given week date.
The week and the day of week should be a negative or a positive number (as a relative week/day from the end of year/week when negative). They should not be zero.
Date.commercial(2001) #=> #<Date: 2001-01-01 ...> Date.commercial(2002) #=> #<Date: 2001-12-31 ...> Date.commercial(2001,5,6) #=> #<Date: 2001-02-03 ...>
See also jd and new.
Returns the calendar week based year.
Date.new(2001,2,3).cwyear #=> 2001 Date.new(2000,1,1).cwyear #=> 1999
Returns true if the date is Monday.
Returns true if the date is Thursday.
Returns the Julian day number denoting the day of calendar reform.
Date.new(2001,2,3).start #=> 2299161.0 Date.new(2001,2,3,Date::GREGORIAN).start #=> -Infinity