Returns the current execution stack—an array containing backtrace location objects.
See Thread::Backtrace::Location for more information.
The optional start parameter determines the number of initial stack entries to omit from the top of the stack.
A second optional length parameter can be used to limit how many entries are returned from the stack.
Returns nil if start is greater than the size of current execution stack.
Optionally you can pass a range, which will return an array containing the entries within the specified range.
Parse a file at filename. Returns the Psych::Nodes::Document.
Raises a Psych::SyntaxError when a YAML syntax error is detected.
Parse a YAML string in yaml. Returns the Psych::Nodes::Stream. This method can handle multiple YAML documents contained in yaml. filename is used in the exception message if a Psych::SyntaxError is raised.
If a block is given, a Psych::Nodes::Document node will be yielded to the block as it’s being parsed.
Raises a Psych::SyntaxError when a YAML syntax error is detected.
Example:
Psych.parse_stream("---\n - a\n - b") # => #<Psych::Nodes::Stream:0x00> Psych.parse_stream("--- a\n--- b") do |node| node # => #<Psych::Nodes::Document:0x00> end begin Psych.parse_stream("--- `", "file.txt") rescue Psych::SyntaxError => ex ex.file # => 'file.txt' ex.message # => "(file.txt): found character that cannot start any token" end
See Psych::Nodes for more information about YAML AST.
Returns the version of libyaml being used
Returns the string which represents the version of zlib library.
def_exception(n, m, s)
n: exception_name
m: message_form
s: superclass(default: StandardError)
define exception named ``c'' with message m.
Remove all observers associated with this object.
Return the number of observers associated with this object.
A Gem::Version for the currently running Ruby.
A Gem::Version for the currently running RubyGems
How String Gem paths should be split. Overridable for esoteric platforms.
Sends a OPTIONS request to the path and gets a response, as an HTTPResponse object.
Create on demand parser.
returns the parser to be used.
Unless a URI::Parser is defined, then DEFAULT_PARSER is used.
Returns a new array containing self‘s elements in reverse order.
[ "a", "b", "c" ].reverse #=> ["c", "b", "a"] [ 1 ].reverse #=> [1]
Reverses self in place.
a = [ "a", "b", "c" ] a.reverse! #=> ["c", "b", "a"] a #=> ["c", "b", "a"]
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 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.
Returns a new string with the characters from str in reverse order.
"stressed".reverse #=> "desserts"
Reverses str in place.
Returns a simpler approximation of the value (flt-|eps| <= result <= flt+|eps|). if the optional eps is not given, it will be chosen automatically.
0.3.rationalize #=> (3/10) 1.333.rationalize #=> (1333/1000) 1.333.rationalize(0.01) #=> (4/3)
See to_r.
Returns the value as a rational. The optional argument eps is always ignored.
Returns a simpler approximation of the value if the optional argument eps is given (rat-|eps| <= result <= rat+|eps|), self otherwise.
r = Rational(5033165, 16777216) r.rationalize #=> (5033165/16777216) r.rationalize(Rational('0.01')) #=> (3/10) r.rationalize(Rational('0.1')) #=> (1/3)