Returns a new array with the concatenated results of running block once for every element in enum.
If no block is given, an enumerator is returned instead.
[1, 2, 3, 4].flat_map { |e| [e, -e] } #=> [1, -1, 2, -2, 3, -3, 4, -4] [[1, 2], [3, 4]].flat_map { |e| e + [100] } #=> [1, 2, 100, 3, 4, 100]
Returns a two element array containing the objects in enum that correspond to the minimum and maximum values respectively from the given block.
If no block is given, an enumerator is returned instead.
a = %w(albatross dog horse) a.minmax_by { |x| x.length } #=> ["dog", "albatross"]
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.
Returns the number of malloc() allocations.
Only available if ruby was built with CALC_EXACT_MALLOC_SIZE
.
Retrieves the server with the given uri
.
See also regist_server
and remove_server.
Generates the Makefile for your extension, passing along any options and preprocessor constants that you may have generated through other methods.
The target
name should correspond the name of the global function name defined within your C extension, minus the Init_
. For example, if your C extension is defined as Init_foo
, then your target would simply be “foo”.
If any “/” characters are present in the target name, only the last name is interpreted as the target name, and the rest are considered toplevel directory names, and the generated Makefile will be altered accordingly to follow that directory structure.
For example, if you pass “test/foo” as a target name, your extension will be installed under the “test” directory. This means that in order to load the file within a Ruby program later, that directory structure will have to be followed, e.g. require 'test/foo'
.
The srcprefix
should be used when your source files are not in the same directory as your build script. This will not only eliminate the need for you to manually copy the source files into the same directory as your build script, but it also sets the proper target_prefix
in the generated Makefile.
Setting the target_prefix
will, in turn, install the generated binary in a directory under your RbConfig::CONFIG['sitearchdir']
that mimics your local filesystem when you run make install
.
For example, given the following file tree:
ext/ extconf.rb test/ foo.c
And given the following code:
create_makefile('test/foo', 'test')
That will set the target_prefix
in the generated Makefile to “test”. That, in turn, will create the following file tree when installed via the make install
command:
/path/to/ruby/sitearchdir/test/foo.so
It is recommended that you use this approach to generate your makefiles, instead of copying files around manually, because some third party libraries may depend on the target_prefix
being set properly.
The srcprefix
argument can be used to override the default source directory, i.e. the current directory. It is included as part of the VPATH
and added to the list of INCFLAGS
.
How String Gem paths should be split. Overridable for esoteric platforms.
Downloads uri
to path
if necessary. If no path is given, it just passes the data.
Returns a relative path from the given base_directory
to the receiver.
If self
is absolute, then base_directory
must be absolute too.
If self
is relative, then base_directory
must be relative too.
This method doesn’t access the filesystem. It assumes no symlinks.
ArgumentError
is raised when it cannot find a relative path.
Returns the class for the given object
.
class A def foo ObjectSpace::trace_object_allocations do obj = Object.new p "#{ObjectSpace::allocation_class_path(obj)}" end end end A.new.foo #=> "Class"
See ::trace_object_allocations
for more information and examples.
Returns the size of memory allocated by malloc().
Only available if ruby was built with CALC_EXACT_MALLOC_SIZE
.
Deduce Ruby’s –program-prefix and –program-suffix from its install name
Should be implemented by a extended class.
tsort_each_child
is used to iterate for child nodes of node.
Returns a new lazy enumerator with the concatenated results of running block once for every element in lazy.
["foo", "bar"].lazy.flat_map {|i| i.each_char.lazy}.force #=> ["f", "o", "o", "b", "a", "r"]
A value x returned by block is decomposed if either of the following conditions is true:
a) <i>x</i> responds to both each and force, which means that <i>x</i> is a lazy enumerator. b) <i>x</i> is an array or responds to to_ary.
Otherwise, x is contained as-is in the return value.
[{a:1}, {b:2}].lazy.flat_map {|i| i}.force #=> [{:a=>1}, {:b=>2}]
See Zlib::GzipReader
documentation for a description.
Returns the eigenvector matrix V
Returns the block diagonal eigenvalue matrix D
Similar to fetch()
, but set
contains unique identifiers.
Yields each message to the passed-in block in turn. Equivalent to:
pop3.mails.each do |popmail| .... end
This method raises a POPError
if an error occurs.