Returns whether the [position] is at the beginning of a line; that is, at the beginning of the [stored string] or immediately after a newline:
scanner = StringScanner.new(MULTILINE_TEXT) scanner.string # => "Go placidly amid the noise and haste,\nand remember what peace there may be in silence.\n" scanner.pos # => 0 scanner.beginning_of_line? # => true scanner.scan_until(/,/) # => "Go placidly amid the noise and haste," scanner.beginning_of_line? # => false scanner.scan(/\n/) # => "\n" scanner.beginning_of_line? # => true scanner.terminate scanner.beginning_of_line? # => true scanner.concat('x') scanner.terminate scanner.beginning_of_line? # => false
StringScanner#bol? is an alias for StringScanner#beginning_of_line?.
Returns the status of the global “abort on exception” condition.
The default is false.
When set to true, if any thread is aborted by an exception, the raised exception will be re-raised in the main thread.
Can also be specified by the global $DEBUG flag or command line option -d.
See also ::abort_on_exception=.
There is also an instance level method to set this for a specific thread, see abort_on_exception.
When set to true, if any thread is aborted by an exception, the raised exception will be re-raised in the main thread. Returns the new state.
Thread.abort_on_exception = true t1 = Thread.new do puts "In new thread" raise "Exception from thread" end sleep(1) puts "not reached"
This will produce:
In new thread prog.rb:4: Exception from thread (RuntimeError) from prog.rb:2:in `initialize' from prog.rb:2:in `new' from prog.rb:2
See also ::abort_on_exception.
There is also an instance level method to set this for a specific thread, see abort_on_exception=.
Returns the status of the global “report on exception” condition.
The default is true since Ruby 2.5.
All threads created when this flag is true will report a message on $stderr if an exception kills the thread.
Thread.new { 1.times { raise } }
will produce this output on $stderr:
#<Thread:...> terminated with exception (report_on_exception is true):
Traceback (most recent call last):
2: from -e:1:in `block in <main>'
1: from -e:1:in `times'
This is done to catch errors in threads early. In some cases, you might not want this output. There are multiple ways to avoid the extra output:
If the exception is not intended, the best is to fix the cause of the exception so it does not happen anymore.
If the exception is intended, it might be better to rescue it closer to where it is raised rather then let it kill the Thread.
If it is guaranteed the Thread will be joined with Thread#join or Thread#value, then it is safe to disable this report with Thread.current.report_on_exception = false when starting the Thread. However, this might handle the exception much later, or not at all if the Thread is never joined due to the parent thread being blocked, etc.
See also ::report_on_exception=.
There is also an instance level method to set this for a specific thread, see report_on_exception=.
Returns the new state. When set to true, all threads created afterwards will inherit the condition and report a message on $stderr if an exception kills a thread:
Thread.report_on_exception = true t1 = Thread.new do puts "In new thread" raise "Exception from thread" end sleep(1) puts "In the main thread"
This will produce:
In new thread #<Thread:...prog.rb:2> terminated with exception (report_on_exception is true): Traceback (most recent call last): prog.rb:4:in `block in <main>': Exception from thread (RuntimeError) In the main thread
See also ::report_on_exception.
There is also an instance level method to set this for a specific thread, see report_on_exception=.
Returns the status of the thread-local “abort on exception” condition for this thr.
The default is false.
See also abort_on_exception=.
There is also a class level method to set this for all threads, see ::abort_on_exception.
When set to true, if this thr is aborted by an exception, the raised exception will be re-raised in the main thread.
See also abort_on_exception.
There is also a class level method to set this for all threads, see ::abort_on_exception=.
Returns the status of the thread-local “report on exception” condition for this thr.
The default value when creating a Thread is the value of the global flag Thread.report_on_exception.
See also report_on_exception=.
There is also a class level method to set this for all new threads, see ::report_on_exception=.
When set to true, a message is printed on $stderr if an exception kills this thr. See ::report_on_exception for details.
See also report_on_exception.
There is also a class level method to set this for all new threads, see ::report_on_exception=.
Establishes proc on thr as the handler for tracing, or disables tracing if the parameter is nil.
Adds proc as a handler for tracing.
Establishes proc as the handler for tracing, or disables tracing if the parameter is nil.
Note: this method is obsolete, please use TracePoint instead.
proc takes up to six parameters:
an event name string
a filename string
a line number
a method name symbol, or nil
a binding, or nil
the class, module, or nil
proc is invoked whenever an event occurs.
Events are:
"c-call"call a C-language routine
"c-return"return from a C-language routine
"call"call a Ruby method
"class"start a class or module definition
"end"finish a class or module definition
"line"execute code on a new line
"raise"raise an exception
"return"return from a Ruby method
Tracing is disabled within the context of proc.
class Test def test a = 1 b = 2 end end set_trace_func proc { |event, file, line, id, binding, class_or_module| printf "%8s %s:%-2d %16p %14p\n", event, file, line, id, class_or_module } t = Test.new t.test
Produces:
c-return prog.rb:8 :set_trace_func Kernel
line prog.rb:11 nil nil
c-call prog.rb:11 :new Class
c-call prog.rb:11 :initialize BasicObject
c-return prog.rb:11 :initialize BasicObject
c-return prog.rb:11 :new Class
line prog.rb:12 nil nil
call prog.rb:2 :test Test
line prog.rb:3 :test Test
line prog.rb:4 :test Test
return prog.rb:5 :test Test
Starts tracing object allocations from the ObjectSpace extension module.
For example:
require 'objspace' class C include ObjectSpace def foo trace_object_allocations do obj = Object.new p "#{allocation_sourcefile(obj)}:#{allocation_sourceline(obj)}" end end end C.new.foo #=> "objtrace.rb:8"
This example has included the ObjectSpace module to make it easier to read, but you can also use the ::trace_object_allocations notation (recommended).
Note that this feature introduces a huge performance decrease and huge memory consumption.
Returns the value of Gem.source_date_epoch_string, as a Time object.
This is used throughout RubyGems for enabling reproducible builds.
Path to specification files of default gems.
The default signing certificate chain path
Shortcut for defining multiple delegator methods, but with no provision for using a different name. The following two code samples have the same effect:
def_delegators :@records, :size, :<<, :map def_delegator :@records, :size def_delegator :@records, :<< def_delegator :@records, :map
Define method as delegator instance method with an optional alias name ali. Method calls to ali will be delegated to accessor.method. accessor should be a method name, instance variable name, or constant name. Use the full path to the constant if providing the constant name. Returns the name of the method defined.
class MyQueue CONST = 1 extend Forwardable attr_reader :queue def initialize @queue = [] end def_delegator :@queue, :push, :mypush def_delegator 'MyQueue::CONST', :to_i end q = MyQueue.new q.mypush 42 q.queue #=> [42] q.push 23 #=> NoMethodError q.to_i #=> 1
Mirror the Prism.parse_file_success? API by using the serialization API.
Returns the string that is used to insert a space between the tokens in a JSON string.
Sets space to the string that is used to insert a space between the tokens in a JSON string.
If this boolean is false, types unsupported by the JSON format will be serialized as strings. If this boolean is true, types unsupported by the JSON format will raise a JSON::GeneratorError.
If this boolean is false, types unsupported by the JSON format will be serialized as strings. If this boolean is true, types unsupported by the JSON format will raise a JSON::GeneratorError.
This sets whether or not to serialize types unsupported by the JSON format as strings. If this boolean is false, types unsupported by the JSON format will be serialized as strings. If this boolean is true, types unsupported by the JSON format will raise a JSON::GeneratorError.
Whether the critical flag is set on this property.