Pushes back one character (passed as a parameter) onto ios, such that a subsequent buffered character read will return it. Only one character may be pushed back before a subsequent read operation (that is, you will be able to read only the last of several characters that have been pushed back). Has no effect with unbuffered reads (such as IO#sysread).
f = File.new("testfile") #=> #<File:testfile> c = f.getc #=> "8" f.ungetc(c) #=> nil f.getc #=> "8"
Positions ios to the beginning of input, resetting lineno to zero.
f = File.new("testfile") f.readline #=> "This is line one\n" f.rewind #=> 0 f.lineno #=> 0 f.readline #=> "This is line one\n"
Note that it cannot be used with streams such as pipes, ttys, and sockets.
Puts ios into binary mode. Once a stream is in binary mode, it cannot be reset to nonbinary mode.
newline conversion disabled
encoding conversion disabled
content is treated as ASCII-8BIT
Returns true if ios is binmode.
Return a string describing this IO object.
Associates the value value with the specified key.
Returns the number of key-value pairs in this database.
Returns a hash created by using gdbm’s values as keys, and the keys as values.
Turns the database’s fast mode on or off. If fast mode is turned on, gdbm does not wait for writes to be flushed to the disk before continuing.
This option is obsolete for gdbm >= 1.8 since fast mode is turned on by default. See also: syncmode=
Returns true if the given key k exists within the database. Returns false otherwise.
Returns a string containing a detailed summary of the keys and values.
Iterates over the range, passing each nth element to the block. If begin and end are numeric, n is added for each iteration. Otherwise step invokes succ to iterate through range elements.
If no block is given, an enumerator is returned instead. Especially, the enumerator is an Enumerator::ArithmeticSequence if begin and end of the range are numeric.
range = Xs.new(1)..Xs.new(10) range.step(2) {|x| puts x} puts range.step(3) {|x| puts x}
produces:
1 x 3 xxx 5 xxxxx 7 xxxxxxx 9 xxxxxxxxx 1 x 4 xxxx 7 xxxxxxx 10 xxxxxxxxxx
See Range for the definition of class Xs.
Returns the first object in the range, or an array of the first n elements.
(10..20).first #=> 10 (10..20).first(3) #=> [10, 11, 12]
Returns the last object in the range, or an array of the last n elements.
Note that with no arguments last will return the object that defines the end of the range even if exclude_end? is true.
(10..20).last #=> 20 (10...20).last #=> 20 (10..20).last(3) #=> [18, 19, 20] (10...20).last(3) #=> [17, 18, 19]
Returns the minimum value in the range. Returns nil if the begin value of the range is larger than the end value. Returns nil if the begin value of an exclusive range is equal to the end value.
Can be given an optional block to override the default comparison method a <=> b.
(10..20).min #=> 10
Returns a two element array which contains the minimum and the maximum value in the range.
Can be given an optional block to override the default comparison method a <=> b.
Convert this range object to a printable form (using inspect to convert the begin and end objects).
Returns true if obj is an element of the range, false otherwise.
("a".."z").include?("g") #=> true ("a".."z").include?("A") #=> false ("a".."z").include?("cc") #=> false
If you need to ensure obj is between begin and end, use cover?
("a".."z").cover?("cc") #=> true
If begin and end are numeric, include? behaves like cover?
(1..3).include?(1.5) # => true
Produce a nicely formatted string-version of rxp. Perhaps surprisingly, #inspect actually produces the more natural version of the string than #to_s.
/ab+c/ix.inspect #=> "/ab+c/ix"
Returns true if the set contains the given object.
Note that include? and member? do not test member equality using == as do other Enumerables.
See also Enumerable#include?
Returns true if the set and the given set have at least one element in common.
Set[1, 2, 3].intersect? Set[4, 5] #=> false Set[1, 2, 3].intersect? Set[3, 4] #=> true
Returns true if the set and the given set have no element in common. This method is the opposite of intersect?.
Set[1, 2, 3].disjoint? Set[3, 4] #=> false Set[1, 2, 3].disjoint? Set[4, 5] #=> true
Deletes every element that appears in the given enumerable object and returns self.