Check if gem name
version version
is installed.
True if the requested gem has already been installed.
Installing a git gem only involves building the extensions and generating the executables.
This is a null install as this specification is already installed. options
are ignored.
This is a null install as a locked specification is considered installed. options
are ignored.
Installs this specification using the Gem::Installer
options
. The install method yields a Gem::Installer
instance, which indicates the gem will be installed, or nil
, which indicates the gem is already installed.
After installation spec
is updated to point to the just-installed specification.
This is a null install as this gem was unpacked into a directory. options
are ignored.
This integer returns the maximum level of data structure nesting in the generated JSON
, max_nesting
= 0 if no maximum is checked.
This sets the maximum level of data structure nesting in the generated JSON
to the integer depth, max_nesting
= 0 if no maximum should be checked.
Checks if ios
starts with a BOM, and then consumes it and sets the external encoding. Returns the result encoding if found, or nil. If ios
is not binmode or its encoding has been set already, an exception will be raised.
File.write("bom.txt", "\u{FEFF}abc") ios = File.open("bom.txt", "rb") ios.set_encoding_by_bom #=> #<Encoding:UTF-8> File.write("nobom.txt", "abc") ios = File.open("nobom.txt", "rb") ios.set_encoding_by_bom #=> nil
Re-composes a prime factorization and returns the product.
pd
Array
of pairs of integers. The each internal pair consists of a prime number – a prime factor – and a natural number – an exponent.
For [[p_1, e_1], [p_2, e_2], ...., [p_n, e_n]]
, it returns:
p_1**e_1 * p_2**e_2 * .... * p_n**e_n. Prime.int_from_prime_division([[2,2], [3,1]]) #=> 12
Starts tracing object allocations.