Returns true if the content needs to be encoded in base64.
Returns the modulo after division of float
by other
.
6543.21.modulo(137) #=> 104.21000000000004 6543.21.modulo(137.24) #=> 92.92999999999961
Returns garbage collector generation for the given object
.
class B include ObjectSpace def foo trace_object_allocations do obj = Object.new p "Generation is #{allocation_generation(obj)}" end end end B.new.foo #=> "Generation is 3"
See ::trace_object_allocations
for more information and examples.
Searches sep or pattern (regexp) in the string and returns the part before it, the match, and the part after it. If it is not found, returns two empty strings and str.
"hello".partition("l") #=> ["he", "l", "lo"] "hello".partition("x") #=> ["hello", "", ""] "hello".partition(/.l/) #=> ["h", "el", "lo"]
Searches sep or pattern (regexp) in the string from the end of the string, and returns the part before it, the match, and the part after it. If it is not found, returns two empty strings and str.
"hello".rpartition("l") #=> ["hel", "l", "o"] "hello".rpartition("x") #=> ["", "", "hello"] "hello".rpartition(/.l/) #=> ["he", "ll", "o"]
Opens a new transaction for the data store. Code executed inside a block passed to this method may read and write data to and from the data store file.
At the end of the block, changes are committed to the data store automatically. You may exit the transaction early with a call to either PStore#commit
or PStore#abort
. See those methods for details about how changes are handled. Raising an uncaught Exception
in the block is equivalent to calling PStore#abort
.
If read_only is set to true
, you will only be allowed to read from the data store during the transaction and any attempts to change the data will raise a PStore::Error
.
Note that PStore
does not support nested transactions.
Returns two arrays, the first containing the elements of enum for which the block evaluates to true, the second containing the rest.
If no block is given, an enumerator is returned instead.
(1..6).partition { |v| v.even? } #=> [[2, 4, 6], [1, 3, 5]]
The standard configuration object for gems.
Use the given configuration object (which implements the ConfigFile
protocol) as the standard configuration object.
Returns the fractional part of the second.
DateTime.new(2001,2,3,4,5,6.5).sec_fraction #=> (1/2)
Specifies a Proc
object proc
to determine if a character in the user’s input is escaped. It should take the user’s input and the index of the character in question as input, and return a boolean (true if the specified character is escaped).
Readline
will only call this proc with characters specified in completer_quote_characters
, to discover if they indicate the end of a quoted argument, or characters specified in completer_word_break_characters
, to discover if they indicate a break between arguments.
If completer_quote_characters
is not set, or if the user input doesn’t contain one of the completer_quote_characters
or a ++ character, Readline
will not attempt to use this proc at all.
Raises ArgumentError
if proc
does not respond to the call method.
Returns the quoting detection Proc
object.
Returns the fractional part of the day.
DateTime.new(2001,2,3,12).day_fraction #=> (1/2)
Returns the fractional part of the second.
DateTime.new(2001,2,3,4,5,6.5).sec_fraction #=> (1/2)
Raises PStore::Error
if the calling code is not in a PStore#transaction
.
When invoked with a block, yield all permutations of length n
of the elements of the array, then return the array itself.
If n
is not specified, yield all permutations of all elements.
The implementation makes no guarantees about the order in which the permutations are yielded.
If no block is given, an Enumerator
is returned instead.
Examples:
a = [1, 2, 3] a.permutation.to_a #=> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]] a.permutation(1).to_a #=> [[1],[2],[3]] a.permutation(2).to_a #=> [[1,2],[1,3],[2,1],[2,3],[3,1],[3,2]] a.permutation(3).to_a #=> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]] a.permutation(0).to_a #=> [[]] # one permutation of length 0 a.permutation(4).to_a #=> [] # no permutations of length 4
When invoked with a block, yields all combinations of length n
of elements from the array and then returns the array itself.
The implementation makes no guarantees about the order in which the combinations are yielded.
If no block is given, an Enumerator
is returned instead.
Examples:
a = [1, 2, 3, 4] a.combination(1).to_a #=> [[1],[2],[3],[4]] a.combination(2).to_a #=> [[1,2],[1,3],[1,4],[2,3],[2,4],[3,4]] a.combination(3).to_a #=> [[1,2,3],[1,2,4],[1,3,4],[2,3,4]] a.combination(4).to_a #=> [[1,2,3,4]] a.combination(0).to_a #=> [[]] # one combination of length 0 a.combination(5).to_a #=> [] # no combinations of length 5
Returns the value as a rational. The optional argument eps
is always ignored.
Returns the value as a rational if possible (the imaginary part should be exactly zero).
Complex(1.0/3, 0).rationalize #=> (1/3) Complex(1, 0.0).rationalize # RangeError Complex(1, 2).rationalize # RangeError
See to_r.
Returns zero as a rational. The optional argument eps
is always ignored.