Gemified in 2.5

The following libraries were made standard gems with Ruby 2.5:

Default Gems

Gem Description Resources
cmath Trigonometric and transcendental functions for complex numbers RubyGems, GitHub, MRI, RDoc
csv Support for CSV (Comma-separated Values) RubyGems, GitHub, MRI (1), MRI (2), RDoc
date c The Date and DateTime classes RubyGems, GitHub, MRI, RDoc (1), RDoc (2)
dbm c Support for DBM databases RubyGems, GitHub, MRI, RDoc
etc c Access UNIX info from /etc RubyGems, GitHub, MRI, RDoc
fcntl c Loads values from the OS' fcntl.h to be used for low-level file descriptor manipulation system calls with IO#fcntl and IO.sysopen RubyGems, GitHub, MRI, RDoc
fiddle c Support for FFI (Foreign Function Interface) RubyGems, GitHub, MRI, RDoc
fileutils Utilities for working with the file system, such as copying, moving, or deleting files RubyGems, GitHub, MRI, RDoc
gdbm c Support for GDBM databases RubyGems, GitHub, MRI, RDoc
ipaddr IP address manipulation (IPv4 and IPv6) RubyGems, GitHub, MRI, RDoc
scanf Pure-Ruby scanf implementation RubyGems, GitHub, MRI, RDoc
sdbm c Support for SDBM databases RubyGems, GitHub, MRI, RDoc
stringio c Makes strings behave like IO objects GitHub, MRI, RDoc
strscan c Lexical string scanning GitHub, MRI, RDoc
zlib c Interface to the zlib compression library RubyGems, GitHub, MRI, RDoc

Bundled Gems

No bundled gems were introduced in 2.5.

More Standard Gems

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