Value from exception raised on the :raise
event
Returns an array of the names of global variables.
global_variables.grep /std/ #=> [:$stdin, :$stdout, :$stderr]
Returns the names of the current local variables.
fred = 1 for i in 1..10 # ... end local_variables #=> [:fred, :i]
Returns the last Error
of the current executing Thread
or nil if none
Sets the last Error
of the current executing Thread
to error
Generate a JSON
document from the Ruby data structure obj and return it. This method disables the checks for circles in Ruby objects.
WARNING: Be careful not to pass any Ruby data structures with circles as obj argument because this will cause JSON
to go into an infinite loop.
Generate a JSON
document from the Ruby data structure obj and return it. The returned document is a prettier form of the document returned by unparse.
The opts argument can be used to configure the generator. See the generate method for a more detailed explanation.
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.
Initiates garbage collection, unless manually disabled.
This method is defined with keyword arguments that default to true:
def GC.start(full_mark: true, immediate_sweep: true); end
Use full_mark: false to perform a minor GC
. Use immediate_sweep: false to defer sweeping (use lazy sweep).
Note: These keyword arguments are implementation and version dependent. They are not guaranteed to be future-compatible, and may be ignored if the underlying implementation does not support them.
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.
Initiates garbage collection, unless manually disabled.
This method is defined with keyword arguments that default to true:
def GC.start(full_mark: true, immediate_sweep: true); end
Use full_mark: false to perform a minor GC
. Use immediate_sweep: false to defer sweeping (use lazy sweep).
Note: These keyword arguments are implementation and version dependent. They are not guaranteed to be future-compatible, and may be ignored if the underlying implementation does not support them.
Start a dRuby server locally.
The new dRuby server will become the primary server, even if another server is currently the primary server.
uri
is the URI
for the server to bind to. If nil, the server will bind to random port on the default local host name and use the default dRuby protocol.
front
is the server’s front object. This may be nil.
config
is the configuration for the new server. This may be nil.
See DRbServer::new
.
Start a dRuby server locally.
The new dRuby server will become the primary server, even if another server is currently the primary server.
uri
is the URI
for the server to bind to. If nil, the server will bind to random port on the default local host name and use the default dRuby protocol.
front
is the server’s front object. This may be nil.
config
is the configuration for the new server. This may be nil.
See DRbServer::new
.
Get the ‘current’ server.
In the context of execution taking place within the main thread of a dRuby server (typically, as a result of a remote call on the server or one of its objects), the current server is that server. Otherwise, the current server is the primary server.
If the above rule fails to find a server, a DRbServerNotFound
error is raised.
Get the ‘current’ server.
In the context of execution taking place within the main thread of a dRuby server (typically, as a result of a remote call on the server or one of its objects), the current server is that server. Otherwise, the current server is the primary server.
If the above rule fails to find a server, a DRbServerNotFound
error is raised.
Returns true if the contents of a file a
and a file b
are identical.
FileUtils.compare_file('somefile', 'somefile') #=> true FileUtils.compare_file('/dev/null', '/dev/urandom') #=> false
Returns true if the contents of a file a
and a file b
are identical.
FileUtils.compare_file('somefile', 'somefile') #=> true FileUtils.compare_file('/dev/null', '/dev/urandom') #=> false
Returns true if the contents of a stream a
and b
are identical.
Returns true if the contents of a stream a
and b
are identical.
Returns whether or not the variable var
can be found in the common header files, or within any headers
that you provide. If found, a macro is passed as a preprocessor constant to the compiler using the variable name, in uppercase, prepended with HAVE_
.
To check variables in an additional library, you need to check that library first using have_library()
.
For example, if have_var('foo')
returned true, then the HAVE_FOO
preprocessor macro would be passed to the compiler.
Returns whether or not the given framework
can be found on your system. If found, a macro is passed as a preprocessor constant to the compiler using the framework name, in uppercase, prepended with HAVE_FRAMEWORK_
.
For example, if have_framework('Ruby')
returned true, then the HAVE_FRAMEWORK_RUBY
preprocessor macro would be passed to the compiler.
If fw
is a pair of the framework name and its header file name that header file is checked, instead of the normally used header file which is named same as the framework.
Open3.pipeline_start
starts a list of commands as a pipeline. No pipes are created for stdin of the first command and stdout of the last command.
Open3.pipeline_start(cmd1, cmd2, ... [, opts]) {|wait_threads| ... } wait_threads = Open3.pipeline_start(cmd1, cmd2, ... [, opts]) ...
Each cmd is a string or an array. If it is an array, the elements are passed to Process.spawn
.
cmd: commandline command line string which is passed to a shell [env, commandline, opts] command line string which is passed to a shell [env, cmdname, arg1, ..., opts] command name and one or more arguments (no shell) [env, [cmdname, argv0], arg1, ..., opts] command name and arguments including argv[0] (no shell) Note that env and opts are optional, as for Process.spawn.
Example:
# Run xeyes in 10 seconds. Open3.pipeline_start("xeyes") {|ts| sleep 10 t = ts[0] Process.kill("TERM", t.pid) p t.value #=> #<Process::Status: pid 911 SIGTERM (signal 15)> } # Convert pdf to ps and send it to a printer. # Collect error message of pdftops and lpr. pdf_file = "paper.pdf" printer = "printer-name" err_r, err_w = IO.pipe Open3.pipeline_start(["pdftops", pdf_file, "-"], ["lpr", "-P#{printer}"], :err=>err_w) {|ts| err_w.close p err_r.read # error messages of pdftops and lpr. }
Open3.pipeline_start
starts a list of commands as a pipeline. No pipes are created for stdin of the first command and stdout of the last command.
Open3.pipeline_start(cmd1, cmd2, ... [, opts]) {|wait_threads| ... } wait_threads = Open3.pipeline_start(cmd1, cmd2, ... [, opts]) ...
Each cmd is a string or an array. If it is an array, the elements are passed to Process.spawn
.
cmd: commandline command line string which is passed to a shell [env, commandline, opts] command line string which is passed to a shell [env, cmdname, arg1, ..., opts] command name and one or more arguments (no shell) [env, [cmdname, argv0], arg1, ..., opts] command name and arguments including argv[0] (no shell) Note that env and opts are optional, as for Process.spawn.
Example:
# Run xeyes in 10 seconds. Open3.pipeline_start("xeyes") {|ts| sleep 10 t = ts[0] Process.kill("TERM", t.pid) p t.value #=> #<Process::Status: pid 911 SIGTERM (signal 15)> } # Convert pdf to ps and send it to a printer. # Collect error message of pdftops and lpr. pdf_file = "paper.pdf" printer = "printer-name" err_r, err_w = IO.pipe Open3.pipeline_start(["pdftops", pdf_file, "-"], ["lpr", "-P#{printer}"], :err=>err_w) {|ts| err_w.close p err_r.read # error messages of pdftops and lpr. }