shusseina
Agile Web Development with Rails 7: 'rails new demo' specifying the Rails version has no affect
@rubys
Created the demo app with the following command from page 102:
work> rails new demo
Examined the installation with the following command from page 104:
demo> bin/rails about
Output indicated Rails 7.0.5:
About your application's environment
Rails version 7.0.5
So I deleted the demo directory and ran the command, specifying the version:
rails _7.0.4_ new demo
Command bin/rails about still reports Rails 7.0.5. However, the Gemfile indicates 7.0.4:
gem "rails", "~> 7.0.4"
I presume 7.0.4 vs 7.0.5 is not going to make much of a difference. However, it would be nice to understand what’s going here.
FYI, gem list rails --local output:
*** LOCAL GEMS ***
importmap-rails (1.1.6)
rails (7.0.5, 7.0.4)
rails-dom-testing (2.0.3)
rails-html-sanitizer (1.6.0)
sprockets-rails (3.4.2)
stimulus-rails (1.2.1)
turbo-rails (1.4.0)
Marked As Solved
edward-mb
This is how RubyGems Semantic Versioning with Pessimistic version constraint works
gem "rails", "~> 7.0.4" # means >= 7.0.4 and < 7.1
Semantic versioning boils down to:
- PATCH
0.0.xlevel changes for implementation level detail changes, such as small bug fixes- MINOR
0.x.0level changes for any backwards compatible API changes, such as new functionality/features- MAJOR
x.0.0level changes for backwards incompatible API changes, such as changes that will break existing users code if they update
If you use a version specifier like "~> 7.0.4" bundler will always pick the latest patch of the given version 7.0 of the gem.
Most of the version specifiers, like
>= 1.0, are self-explanatory. The specifier~>has a special meaning, best shown by example.~> 2.0.3is identical to>= 2.0.3and< 2.1.~> 2.1is identical to>= 2.1and< 3.0.~> 2.2.betawill match prerelease versions like2.2.beta.12.~> 0is identical to>= 0.0and< 1.0.
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rubys
I’ve added an explanation and suggested replacing the twiddle-wakka with an equals sign.
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