wkpdf をインストールしたいので、ちゃんと ruby をインストールするところから…と思って、ここ↓の通りにやっってみました。

以下に、ログをコピペしておきます。



bisonSSD840EVO:~ stbison$ brew install git
==> Downloading https://homebrew.bintray.com/bottles/git-2.8.2.el_capitan.bottle
######################################################################## 100.0%
==> Pouring git-2.8.2.el_capitan.bottle.tar.gz
==> Caveats
The OS X keychain credential helper has been installed to:
/usr/local/bin/git-credential-osxkeychain

The "contrib" directory has been installed to:
/usr/local/share/git-core/contrib

Bash completion has been installed to:
/usr/local/etc/bash_completion.d

zsh completion has been installed to:
/usr/local/share/zsh/site-functions

Emacs Lisp files have been installed to:
/usr/local/share/emacs/site-lisp/git
==> Summary
🍺 /usr/local/Cellar/git/2.8.2: 1,418 files, 30.5M
bisonSSD840EVO:~ stbison$ brew install readline
==> Downloading https://homebrew.bintray.com/bottles/readline-6.3.8.el_capitan.b
######################################################################## 100.0%
==> Pouring readline-6.3.8.el_capitan.bottle.tar.gz
==> Caveats
This formula is keg-only, which means it was not symlinked into /usr/local.

OS X provides the BSD libedit library, which shadows libreadline.
In order to prevent conflicts when programs look for libreadline we are
defaulting this GNU Readline installation to keg-only.


Generally there are no consequences of this for you. If you build your
own software and it requires this formula, you'll need to add to your
build variables:

LDFLAGS: -L/usr/local/opt/readline/lib
CPPFLAGS: -I/usr/local/opt/readline/include

==> Summary
🍺 /usr/local/Cellar/readline/6.3.8: 46 files, 2.0M
bisonSSD840EVO:~ stbison$ brew install openssl
==> Downloading https://homebrew.bintray.com/bottles/openssl-1.0.2h.el_capitan.b
######################################################################## 100.0%
==> Pouring openssl-1.0.2h.el_capitan.bottle.tar.gz
==> Caveats
A CA file has been bootstrapped using certificates from the system
keychain. To add additional certificates, place .pem files in
/usr/local/etc/openssl/certs

and run
/usr/local/opt/openssl/bin/c_rehash

This formula is keg-only, which means it was not symlinked into /usr/local.

Apple has deprecated use of OpenSSL in favor of its own TLS and crypto libraries

Generally there are no consequences of this for you. If you build your
own software and it requires this formula, you'll need to add to your
build variables:

LDFLAGS: -L/usr/local/opt/openssl/lib
CPPFLAGS: -I/usr/local/opt/openssl/include

==> Summary
🍺 /usr/local/Cellar/openssl/1.0.2h: 1,691 files, 12M
bisonSSD840EVO:~ stbison$ brew install ruby-build
==> Installing dependencies for ruby-build: autoconf, pkg-config
==> Installing ruby-build dependency: autoconf
==> Downloading https://homebrew.bintray.com/bottles/autoconf-2.69.el_capitan.bo
######################################################################## 100.0%
==> Pouring autoconf-2.69.el_capitan.bottle.4.tar.gz
==> Caveats
Emacs Lisp files have been installed to:
/usr/local/share/emacs/site-lisp/autoconf
==> Summary
🍺 /usr/local/Cellar/autoconf/2.69: 70 files, 3.0M
==> Installing ruby-build dependency: pkg-config
==> Downloading https://homebrew.bintray.com/bottles/pkg-config-0.29.1.el_capita
######################################################################## 100.0%
==> Pouring pkg-config-0.29.1.el_capitan.bottle.tar.gz
🍺 /usr/local/Cellar/pkg-config/0.29.1: 10 files, 627.2K
==> Installing ruby-build
==> Downloading https://github.com/rbenv/ruby-build/archive/v20160426.tar.gz
==> Downloading from https://codeload.github.com/rbenv/ruby-build/tar.gz/v201604
######################################################################## 100.0%
==> ./install.sh
🍺 /usr/local/Cellar/ruby-build/20160426: 215 files, 124.6K, built in 4 seconds
bisonSSD840EVO:~ stbison$ brew install rbenv
==> Downloading https://homebrew.bintray.com/bottles/rbenv-1.0.0.el_capitan.bott
######################################################################## 100.0%
==> Pouring rbenv-1.0.0.el_capitan.bottle.tar.gz
==> Caveats
Rbenv stores data under ~/.rbenv by default. If you absolutely need to
store everything under Homebrew's prefix, include this in your profile:
export RBENV_ROOT=/usr/local/var/rbenv

To enable shims and autocompletion, run this and follow the instructions:
rbenv init
==> Summary
🍺 /usr/local/Cellar/rbenv/1.0.0: 36 files, 61.9K
bisonSSD840EVO:~ stbison$ echo $PATH
/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/opt/X11/bin
bisonSSD840EVO:~ stbison$ echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> .bash_profile
bisonSSD840EVO:~ stbison$ echo 'eval "$(rbenv init -)"' >> .bash_profile
bisonSSD840EVO:~ stbison$ source .bash_profile
bisonSSD840EVO:~ stbison$ rbenv install -l
Available versions:
1.8.6-p383
1.8.6-p420
1.8.7-p249
1.8.7-p302
1.8.7-p334
1.8.7-p352
1.8.7-p357
1.8.7-p358
1.8.7-p370
1.8.7-p371
1.8.7-p374
1.8.7-p375
1.9.1-p378
1.9.1-p430
1.9.2-p0
1.9.2-p180
1.9.2-p290
1.9.2-p318
1.9.2-p320
1.9.2-p326
1.9.2-p330
1.9.3-dev
1.9.3-preview1
1.9.3-rc1
1.9.3-p0
1.9.3-p125
1.9.3-p194
1.9.3-p286
1.9.3-p327
1.9.3-p362
1.9.3-p374
1.9.3-p385
1.9.3-p392
1.9.3-p429
1.9.3-p448
1.9.3-p484
1.9.3-p545
1.9.3-p547
1.9.3-p550
1.9.3-p551
2.0.0-dev
2.0.0-preview1
2.0.0-preview2
2.0.0-rc1
2.0.0-rc2
2.0.0-p0
2.0.0-p195
2.0.0-p247
2.0.0-p353
2.0.0-p451
2.0.0-p481
2.0.0-p576
2.0.0-p594
2.0.0-p598
2.0.0-p643
2.0.0-p645
2.0.0-p647
2.0.0-p648
2.1.0-dev
2.1.0-preview1
2.1.0-preview2
2.1.0-rc1
2.1.0
2.1.1
2.1.2
2.1.3
2.1.4
2.1.5
2.1.6
2.1.7
2.1.8
2.1.9
2.1.10
2.2.0-dev
2.2.0-preview1
2.2.0-preview2
2.2.0-rc1
2.2.0
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.3.0-dev
2.3.0-preview1
2.3.0-preview2
2.3.0
2.3.1
2.4.0-dev
jruby-1.5.6
jruby-1.6.3
jruby-1.6.4
jruby-1.6.5
jruby-1.6.5.1
jruby-1.6.6
jruby-1.6.7
jruby-1.6.7.2
jruby-1.6.8
jruby-1.7.0-preview1
jruby-1.7.0-preview2
jruby-1.7.0-rc1
jruby-1.7.0-rc2
jruby-1.7.0
jruby-1.7.1
jruby-1.7.2
jruby-1.7.3
jruby-1.7.4
jruby-1.7.5
jruby-1.7.6
jruby-1.7.7
jruby-1.7.8
jruby-1.7.9
jruby-1.7.10
jruby-1.7.11
jruby-1.7.12
jruby-1.7.13
jruby-1.7.14
jruby-1.7.15
jruby-1.7.16
jruby-1.7.16.1
jruby-1.7.16.2
jruby-1.7.17
jruby-1.7.18
jruby-1.7.19
jruby-1.7.20
jruby-1.7.20.1
jruby-1.7.21
jruby-1.7.22
jruby-1.7.23
jruby-1.7.24
jruby-1.7.25
jruby-9.0.0.0.pre1
jruby-9.0.0.0.pre2
jruby-9.0.0.0.rc1
jruby-9.0.0.0.rc2
jruby-9.0.0.0
jruby-9.0.1.0
jruby-9.0.3.0
jruby-9.0.4.0
jruby-9.0.5.0
jruby-9.1.0.0-dev
maglev-1.0.0
maglev-1.1.0-dev
maglev-2.0.0-dev
mruby-dev
mruby-1.0.0
mruby-1.1.0
mruby-1.2.0
rbx-2.2.2
rbx-2.2.3
rbx-2.2.4
rbx-2.2.5
rbx-2.2.6
rbx-2.2.7
rbx-2.2.8
rbx-2.2.9
rbx-2.2.10
rbx-2.3.0
rbx-2.4.0
rbx-2.4.1
rbx-2.5.0
rbx-2.5.1
rbx-2.5.2
rbx-2.5.3
rbx-2.5.4
rbx-2.5.5
rbx-2.5.6
rbx-2.5.7
rbx-2.5.8
rbx-2.6
rbx-2.7
rbx-2.8
rbx-2.9
rbx-2.10
rbx-2.11
rbx-2.71828182
rbx-3.0
rbx-3.1
rbx-3.2
rbx-3.3
rbx-3.4
rbx-3.5
rbx-3.6
rbx-3.7
rbx-3.8
rbx-3.9
rbx-3.10
rbx-3.11
rbx-3.12
rbx-3.13
rbx-3.14
rbx-3.15
rbx-3.16
rbx-3.17
rbx-3.18
rbx-3.19
rbx-3.20
rbx-3.21
rbx-3.22
rbx-3.23
rbx-3.24
rbx-3.25
rbx-3.26
rbx-3.27
ree-1.8.7-2011.03
ree-1.8.7-2011.12
ree-1.8.7-2012.01
ree-1.8.7-2012.02
topaz-dev
bisonSSD840EVO:~ stbison$ rbenv install 2.3.1
Downloading ruby-2.3.1.tar.bz2...
-> https://cache.ruby-lang.org/pub/ruby/2.3/ruby-2.3.1.tar.bz2
Installing ruby-2.3.1...

Installed ruby-2.3.1 to /Users/stbison/.rbenv/versions/2.3.1

bisonSSD840EVO:~ stbison$ rbenv global 2.3.1
bisonSSD840EVO:~ stbison$ rbenv versions
system
* 2.3.1 (set by /Users/stbison/.rbenv/version)
bisonSSD840EVO:~ stbison$ ruby -v
ruby 2.3.1p112 (2016-04-26 revision 54768) [x86_64-darwin15]
bisonSSD840EVO:~ stbison$ gem install rails
Fetching: rack-1.6.4.gem (100%)
Successfully installed rack-1.6.4
Fetching: concurrent-ruby-1.0.2.gem (100%)
Successfully installed concurrent-ruby-1.0.2
Fetching: sprockets-3.6.0.gem (100%)
Successfully installed sprockets-3.6.0
Fetching: thread_safe-0.3.5.gem (100%)
Successfully installed thread_safe-0.3.5
Fetching: tzinfo-1.2.2.gem (100%)
Successfully installed tzinfo-1.2.2
Fetching: i18n-0.7.0.gem (100%)
Successfully installed i18n-0.7.0
Fetching: activesupport-4.2.6.gem (100%)
Successfully installed activesupport-4.2.6
Fetching: mini_portile2-2.0.0.gem (100%)
Successfully installed mini_portile2-2.0.0
Fetching: nokogiri-1.6.7.2.gem (100%)
Building native extensions. This could take a while...
Successfully installed nokogiri-1.6.7.2
Fetching: loofah-2.0.3.gem (100%)
Successfully installed loofah-2.0.3
Fetching: rails-html-sanitizer-1.0.3.gem (100%)
Successfully installed rails-html-sanitizer-1.0.3
Fetching: rails-deprecated_sanitizer-1.0.3.gem (100%)
Successfully installed rails-deprecated_sanitizer-1.0.3
Fetching: rails-dom-testing-1.0.7.gem (100%)
Successfully installed rails-dom-testing-1.0.7
Fetching: rack-test-0.6.3.gem (100%)
Successfully installed rack-test-0.6.3
Fetching: erubis-2.7.0.gem (100%)
Successfully installed erubis-2.7.0
Fetching: builder-3.2.2.gem (100%)
Successfully installed builder-3.2.2
Fetching: actionview-4.2.6.gem (100%)
Successfully installed actionview-4.2.6
Fetching: actionpack-4.2.6.gem (100%)
Successfully installed actionpack-4.2.6
Fetching: sprockets-rails-3.0.4.gem (100%)
Successfully installed sprockets-rails-3.0.4
Fetching: thor-0.19.1.gem (100%)
Successfully installed thor-0.19.1
Fetching: railties-4.2.6.gem (100%)
Successfully installed railties-4.2.6
Fetching: bundler-1.12.3.gem (100%)
Successfully installed bundler-1.12.3
Fetching: arel-6.0.3.gem (100%)
Successfully installed arel-6.0.3
Fetching: activemodel-4.2.6.gem (100%)
Successfully installed activemodel-4.2.6
Fetching: activerecord-4.2.6.gem (100%)
Successfully installed activerecord-4.2.6
Fetching: globalid-0.3.6.gem (100%)
Successfully installed globalid-0.3.6
Fetching: activejob-4.2.6.gem (100%)
Successfully installed activejob-4.2.6
Fetching: mime-types-data-3.2016.0221.gem (100%)
Successfully installed mime-types-data-3.2016.0221
Fetching: mime-types-3.0.gem (100%)
Successfully installed mime-types-3.0
Fetching: mail-2.6.4.gem (100%)
Successfully installed mail-2.6.4
Fetching: actionmailer-4.2.6.gem (100%)
Successfully installed actionmailer-4.2.6
Fetching: rails-4.2.6.gem (100%)
Successfully installed rails-4.2.6
Parsing documentation for rack-1.6.4
Installing ri documentation for rack-1.6.4
Parsing documentation for concurrent-ruby-1.0.2
Installing ri documentation for concurrent-ruby-1.0.2
Parsing documentation for sprockets-3.6.0
Installing ri documentation for sprockets-3.6.0
Parsing documentation for thread_safe-0.3.5
Installing ri documentation for thread_safe-0.3.5
Parsing documentation for tzinfo-1.2.2
Installing ri documentation for tzinfo-1.2.2
Parsing documentation for i18n-0.7.0
Installing ri documentation for i18n-0.7.0
Parsing documentation for activesupport-4.2.6
Installing ri documentation for activesupport-4.2.6
Parsing documentation for mini_portile2-2.0.0
Installing ri documentation for mini_portile2-2.0.0
Parsing documentation for nokogiri-1.6.7.2
Installing ri documentation for nokogiri-1.6.7.2
Parsing documentation for loofah-2.0.3
Installing ri documentation for loofah-2.0.3
Parsing documentation for rails-html-sanitizer-1.0.3
Installing ri documentation for rails-html-sanitizer-1.0.3
Parsing documentation for rails-deprecated_sanitizer-1.0.3
Installing ri documentation for rails-deprecated_sanitizer-1.0.3
Parsing documentation for rails-dom-testing-1.0.7
Installing ri documentation for rails-dom-testing-1.0.7
Parsing documentation for rack-test-0.6.3
Installing ri documentation for rack-test-0.6.3
Parsing documentation for erubis-2.7.0
Installing ri documentation for erubis-2.7.0
Parsing documentation for builder-3.2.2
Installing ri documentation for builder-3.2.2
Parsing documentation for actionview-4.2.6
Installing ri documentation for actionview-4.2.6
Parsing documentation for actionpack-4.2.6
Installing ri documentation for actionpack-4.2.6
Parsing documentation for sprockets-rails-3.0.4
Installing ri documentation for sprockets-rails-3.0.4
Parsing documentation for thor-0.19.1
Installing ri documentation for thor-0.19.1
Parsing documentation for railties-4.2.6
Installing ri documentation for railties-4.2.6
Parsing documentation for bundler-1.12.3
Installing ri documentation for bundler-1.12.3
Parsing documentation for arel-6.0.3
Installing ri documentation for arel-6.0.3
Parsing documentation for activemodel-4.2.6
Installing ri documentation for activemodel-4.2.6
Parsing documentation for activerecord-4.2.6
Installing ri documentation for activerecord-4.2.6
Parsing documentation for globalid-0.3.6
Installing ri documentation for globalid-0.3.6
Parsing documentation for activejob-4.2.6
Installing ri documentation for activejob-4.2.6
Parsing documentation for mime-types-data-3.2016.0221
Installing ri documentation for mime-types-data-3.2016.0221
Parsing documentation for mime-types-3.0
Installing ri documentation for mime-types-3.0
Parsing documentation for mail-2.6.4
Installing ri documentation for mail-2.6.4
Parsing documentation for actionmailer-4.2.6
Installing ri documentation for actionmailer-4.2.6
Parsing documentation for rails-4.2.6
Installing ri documentation for rails-4.2.6
Done installing documentation for rack, concurrent-ruby, sprockets, thread_safe, tzinfo, i18n, activesupport, mini_portile2, nokogiri, loofah, rails-html-sanitizer, rails-deprecated_sanitizer, rails-dom-testing, rack-test, erubis, builder, actionview, actionpack, sprockets-rails, thor, railties, bundler, arel, activemodel, activerecord, globalid, activejob, mime-types-data, mime-types, mail, actionmailer, rails after 589 seconds
32 gems installed
bisonSSD840EVO:~ stbison$ gem install bundler
Successfully installed bundler-1.12.3
Parsing documentation for bundler-1.12.3
Done installing documentation for bundler after 6 seconds
1 gem installed
bisonSSD840EVO:~ stbison$ rbenv rehash
bisonSSD840EVO:~ stbison$ source ~/.bash_profile
bisonSSD840EVO:~ stbison$ rails -v
Rails 4.2.6