Creates a temporary file as usual File
object (not Tempfile
). It doesn’t use finalizer and delegation.
If no block is given, this is similar to Tempfile.new
except creating File
instead of Tempfile
. The created file is not removed automatically. You should use File.unlink
to remove it.
If a block is given, then a File
object will be constructed, and the block is invoked with the object as the argument. The File
object will be automatically closed and the temporary file is removed after the block terminates. The call returns the value of the block.
In any case, all arguments (+*args+) will be treated as Tempfile.new
.
Tempfile.create('foo', '/home/temp') do |f| ... do something with f ... end
Returns the main thread.
Terminates thr
and schedules another thread to be run.
If this thread is already marked to be killed, exit
returns the Thread
.
If this is the main thread, or the last thread, exits the process.
Returns the status of thr
.
"sleep"
Returned if this thread is sleeping or waiting on I/O
"run"
When this thread is executing
"aborting"
If this thread is aborting
false
When this thread is terminated normally
nil
If terminated with an exception.
a = Thread.new { raise("die now") } b = Thread.new { Thread.stop } c = Thread.new { Thread.exit } d = Thread.new { sleep } d.kill #=> #<Thread:0x401b3678 aborting> a.status #=> nil b.status #=> "sleep" c.status #=> false d.status #=> "aborting" Thread.current.status #=> "run"
Path of the file being run
Returns internal information of TracePoint
.
The contents of the returned value are implementation specific. It may be changed in future.
This method is only for debugging TracePoint
itself.
See also BigDecimal.new
Creates a new Pathname
object from the given string, path
, and returns pathname object.
In order to use this constructor, you must first require the Pathname
standard library extension.
require 'pathname' Pathname("/home/zzak") #=> #<Pathname:/home/zzak>
See also Pathname::new
for more information.
Equivalent to:
$stdout.putc(int)
Refer to the documentation for IO#putc
for important information regarding multi-byte characters.
Returns arg converted to a float. Numeric
types are converted directly, and with exception to string and nil the rest are converted using arg.to_f. Converting a string
with invalid characters will result in a ArgumentError
. Converting nil
generates a TypeError
.
Float(1) #=> 1.0 Float("123.456") #=> 123.456 Float("123.0_badstring") #=> ArgumentError: invalid value for Float(): "123.0_badstring" Float(nil) #=> TypeError: can't convert nil into Float
Returns x/y;
Rational(1, 2) #=> (1/2) Rational('1/2') #=> (1/2) Rational(nil) #=> TypeError Rational(1, nil) #=> TypeError
Syntax of string form:
string form = extra spaces , rational , extra spaces ; rational = [ sign ] , unsigned rational ; unsigned rational = numerator | numerator , "/" , denominator ; numerator = integer part | fractional part | integer part , fractional part ; denominator = digits ; integer part = digits ; fractional part = "." , digits , [ ( "e" | "E" ) , [ sign ] , digits ] ; sign = "-" | "+" ; digits = digit , { digit | "_" , digit } ; digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ; extra spaces = ? \s* ? ;
See String#to_r
.
Equivalent to ($_.dup).chop!
, except nil
is never returned. See String#chop!
. Available only when -p/-n command line option specified.
Equivalent to $_ = $_.chomp(string)
. See String#chomp
. Available only when -p/-n command line option specified.
Returns true
if yield
would execute a block in the current context. The iterator?
form is mildly deprecated.
def try if block_given? yield else "no block" end end try #=> "no block" try { "hello" } #=> "hello" try do "hello" end #=> "hello"
Returns a new array with the results of running block once for every element in enum.
If no block is given, an enumerator is returned instead.
(1..4).map { |i| i*i } #=> [1, 4, 9, 16] (1..4).collect { "cat" } #=> ["cat", "cat", "cat", "cat"]
Returns the object in enum with the maximum value. The first form assumes all objects implement Comparable
; the second uses the block to return a <=> b.
a = %w(albatross dog horse) a.max #=> "horse" a.max { |a, b| a.length <=> b.length } #=> "albatross"
If the n
argument is given, maximum n
elements are returned as an array, sorted in descending order.
a = %w[albatross dog horse] a.max(2) #=> ["horse", "dog"] a.max(2) {|a, b| a.length <=> b.length } #=> ["albatross", "horse"] [5, 1, 3, 4, 2].max(3) #=> [5, 4, 3]
Enumerates over the items, chunking them together based on the return value of the block.
Consecutive elements which return the same block value are chunked together.
For example, consecutive even numbers and odd numbers can be chunked as follows.
[3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5].chunk { |n| n.even? }.each { |even, ary| p [even, ary] } #=> [false, [3, 1]] # [true, [4]] # [false, [1, 5, 9]] # [true, [2, 6]] # [false, [5, 3, 5]]
This method is especially useful for sorted series of elements. The following example counts words for each initial letter.
open("/usr/share/dict/words", "r:iso-8859-1") { |f| f.chunk { |line| line.ord }.each { |ch, lines| p [ch.chr, lines.length] } } #=> ["\n", 1] # ["A", 1327] # ["B", 1372] # ["C", 1507] # ["D", 791] # ...
The following key values have special meaning:
nil
and :_separator
specifies that the elements should be dropped.
:_alone
specifies that the element should be chunked by itself.
Any other symbols that begin with an underscore will raise an error:
items.chunk { |item| :_underscore } #=> RuntimeError: symbols beginning with an underscore are reserved
nil
and :_separator
can be used to ignore some elements.
For example, the sequence of hyphens in svn log can be eliminated as follows:
sep = "-"*72 + "\n" IO.popen("svn log README") { |f| f.chunk { |line| line != sep || nil }.each { |_, lines| pp lines } } #=> ["r20018 | knu | 2008-10-29 13:20:42 +0900 (Wed, 29 Oct 2008) | 2 lines\n", # "\n", # "* README, README.ja: Update the portability section.\n", # "\n"] # ["r16725 | knu | 2008-05-31 23:34:23 +0900 (Sat, 31 May 2008) | 2 lines\n", # "\n", # "* README, README.ja: Add a note about default C flags.\n", # "\n"] # ...
Paragraphs separated by empty lines can be parsed as follows:
File.foreach("README").chunk { |line| /\A\s*\z/ !~ line || nil }.each { |_, lines| pp lines }
:_alone
can be used to force items into their own chunk. For example, you can put lines that contain a URL by themselves, and chunk the rest of the lines together, like this:
pattern = /http/ open(filename) { |f| f.chunk { |line| line =~ pattern ? :_alone : true }.each { |key, lines| pp lines } }
Computes the arctangent of decimal
to the specified number of digits of precision, numeric
.
If decimal
is NaN, returns NaN.
BigMath.atan(BigDecimal.new('-1'), 16).to_s #=> "-0.785398163397448309615660845819878471907514682065E0"
Allocate size
bytes of memory and return the integer memory address for the allocated memory.
Generate a JSON
document from the Ruby data structure obj and return it. state is * a JSON::State object,
or a Hash
like object (responding to to_hash),
an object convertible into a hash by a to_h method,
that is used as or to configure a State object.
It defaults to a state object, that creates the shortest possible JSON
text in one line, checks for circular data structures and doesn’t allow NaN
, Infinity
, and -Infinity.
A state hash can have the following keys:
indent: a string used to indent levels (default: ”),
space: a string that is put after, a : or , delimiter (default: ”),
space_before: a string that is put before a : pair delimiter (default: ”),
object_nl: a string that is put at the end of a JSON
object (default: ”),
array_nl: a string that is put at the end of a JSON
array (default: ”),
allow_nan: true if NaN
, Infinity
, and -Infinity should be generated, otherwise an exception is thrown if these values are encountered. This options defaults to false.
max_nesting: The maximum depth of nesting allowed in the data structures from which JSON
is to be generated. Disable depth checking with :max_nesting => false, it defaults to 100.
See also the fast_generate
for the fastest creation method with the least amount of sanity checks, and the pretty_generate
method for some defaults for pretty output.
Checks the status of the child process specified by pid
. Returns nil
if the process is still alive.
If the process is not alive, and raise
was true, a PTY::ChildExited
exception will be raised. Otherwise it will return a Process::Status
instance.
pid
The process id of the process to check
raise
If true
and the process identified by pid
is no longer alive a PTY::ChildExited
is raised.
Returns the log priority mask in effect. The mask is not reset by opening or closing syslog.
Sets the log priority mask. A method LOG_UPTO is defined to make it easier to set mask values. Example:
Syslog.mask = Syslog::LOG_UPTO(Syslog::LOG_ERR)
Alternatively, specific priorities can be selected and added together using binary OR. Example:
Syslog.mask = Syslog::LOG_MASK(Syslog::LOG_ERR) | Syslog::LOG_MASK(Syslog::LOG_CRIT)
The priority mask persists through calls to open() and close().
Compresses the given string
. Valid values of level are Zlib::NO_COMPRESSION
, Zlib::BEST_SPEED
, Zlib::BEST_COMPRESSION
, Zlib::DEFAULT_COMPRESSION
, or an integer from 0 to 9.
This method is almost equivalent to the following code:
def deflate(string, level) z = Zlib::Deflate.new(level) dst = z.deflate(string, Zlib::FINISH) z.close dst end
See also Zlib.inflate
Decompresses string
. Raises a Zlib::NeedDict
exception if a preset dictionary is needed for decompression.
This method is almost equivalent to the following code:
def inflate(string) zstream = Zlib::Inflate.new buf = zstream.inflate(string) zstream.finish zstream.close buf end
See also Zlib.deflate