好的，所以我有一个 Rails 应用程序，我试图在 postgres 数据库上运行迁移，我通常使用 mysql，一切都很好，但是当我运行命令时，我得到了这个
rake db:migrate
(in /Users/tamer/Sites/my_app)
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:487: [BUG] Segmentation fault
ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-darwin10.8.0]
-- control frame ----------
c:0058 p:---- s:0215 b:0215 l:000214 d:000214 CFUNC :exec
c:0057 p:0040 s:0211 b:0211 l:000191 d:000210 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter
c:0056 p:0005 s:0208 b:0208 l:000198 d:000207 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract_adapter.r
c:0055 p:0032 s:0206 b:0206 l:000205 d:000205 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activesupport-3.0.3/lib/active_support/notifications/instrumenter.rb:21
c:0054 p:0052 s:0199 b:0199 l:000198 d:000198 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract_adapter.r
c:0053 p:0018 s:0192 b:0192 l:000191 d:000191 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter
c:0052 p:0013 s:0187 b:0187 l:000186 d:000186 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter
c:0051 p:0011 s:0184 b:0184 l:000183 d:000183 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter
c:0050 p:0136 s:0180 b:0180 l:000179 d:000179 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter
c:0049 p:0131 s:0177 b:0177 l:000176 d:000176 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter
c:0048 p:0054 s:0174 b:0174 l:000173 d:000173 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter
c:0047 p:---- s:0167 b:0167 l:000166 d:000166 FINISH
c:0046 p:---- s:0165 b:0165 l:000164 d:000164 CFUNC :new
c:0045 p:0186 s:0158 b:0158 l:000157 d:000157 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter
c:0044 p:0045 s:0149 b:0149 l:000148 d:000148 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0043 p:0011 s:0146 b:0146 l:000145 d:000145 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0042 p:0048 s:0142 b:0142 l:000128 d:000141 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0041 p:---- s:0139 b:0139 l:000138 d:000138 FINISH
c:0040 p:---- s:0137 b:0137 l:000136 d:000136 CFUNC :loop
c:0039 p:0009 s:0134 b:0134 l:000128 d:000133 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0038 p:0019 s:0132 b:0132 l:000131 d:000131 METHOD /Users/tamer/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/monitor.rb:201
c:0037 p:0013 s:0129 b:0129 l:000128 d:000128 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0036 p:0030 s:0126 b:0123 l:000122 d:000122 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0035 p:0033 s:0120 b:0120 l:000119 d:000119 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0034 p:0018 s:0115 b:0115 l:000114 d:000114 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0033 p:0011 s:0112 b:0112 l:000111 d:000111 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connectio
c:0032 p:0020 s:0109 b:0109 l:000108 d:000108 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/migration.rb:486
c:0031 p:---- s:0103 b:0103 l:000102 d:000102 FINISH
c:0030 p:---- s:0101 b:0101 l:000100 d:000100 CFUNC :new
c:0029 p:0020 s:0095 b:0095 l:000094 d:000094 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/migration.rb:433
c:0028 p:0083 s:0090 b:0090 l:000089 d:000089 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/migration.rb:415
c:0027 p:0102 s:0085 b:0085 l:000d58 d:000084 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/railties/databases.rake:142
c:0026 p:---- s:0083 b:0083 l:000082 d:000082 FINISH
c:0025 p:---- s:0081 b:0081 l:000080 d:000080 CFUNC :call
c:0024 p:0043 s:0076 b:0076 l:000067 d:000075 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:636
c:0023 p:---- s:0073 b:0073 l:000072 d:000072 FINISH
c:0022 p:---- s:0071 b:0071 l:000070 d:000070 CFUNC :each
c:0021 p:0171 s:0068 b:0068 l:000067 d:000067 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:631
c:0020 p:0110 s:0064 b:0064 l:000058 d:000063 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:597
c:0019 p:0019 s:0062 b:0062 l:000061 d:000061 METHOD /Users/tamer/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/monitor.rb:201
c:0018 p:0033 s:0059 b:0059 l:000058 d:000058 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:590
c:0017 p:0048 s:0053 b:0053 l:000052 d:000052 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:583
c:0016 p:0045 s:0048 b:0048 l:000047 d:000047 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2051
c:0015 p:0012 s:0041 b:0041 l:000026 d:000040 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2029
c:0014 p:---- s:0038 b:0038 l:000037 d:000037 FINISH
c:0013 p:---- s:0036 b:0036 l:000035 d:000035 CFUNC :each
c:0012 p:0069 s:0033 b:0033 l:000026 d:000032 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2029
c:0011 p:0009 s:0031 b:0031 l:000030 d:000030 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/airbrake-3.0.9/lib/airbrake/rake_handler.rb:33
c:0010 p:0011 s:0027 b:0027 l:000026 d:000026 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2023
c:0009 p:0029 s:0024 b:0024 l:000017 d:000023 BLOCK /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2001
c:0008 p:0009 s:0022 b:0022 l:000021 d:000021 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2068
c:0007 p:0011 s:0018 b:0018 l:000017 d:000017 METHOD /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:1998
c:0006 p:0036 s:0015 b:0015 l:000014 d:000014 TOP /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/bin/rake:31
c:0005 p:---- s:0013 b:0013 l:000012 d:000012 FINISH
c:0004 p:---- s:0011 b:0011 l:000010 d:000010 CFUNC :load
c:0003 p:0127 s:0007 b:0007 l:0014e8 d:000f40 EVAL /Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/bin/rake:19
c:0002 p:---- s:0004 b:0004 l:000003 d:000003 FINISH
c:0001 p:0000 s:0002 b:0002 l:0014e8 d:0014e8 TOP
---------------------------
-- Ruby level backtrace information ----------------------------------------
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/bin/rake:19:in `<main>'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/bin/rake:19:in `load'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/bin/rake:31:in `<top (required)>'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:1998:in `run'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2001:in `block in run'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2023:in `top_level'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/airbrake-3.0.9/lib/airbrake/rake_handler.rb:33:in `standard_exception_handling'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2029:in `block in top_level'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2029:in `each'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2029:in `block (2 levels) in top_level'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:2051:in `invoke_task'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:583:in `invoke'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:590:in `invoke_with_call_chain'
/Users/tamer/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:597:in `block in invoke_with_call_chain'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:631:in `execute'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:631:in `each'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:636:in `block in execute'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/rake-0.8.7/lib/rake.rb:636:in `call'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/railties/databases.rake:142:in `block (2 levels) in <top (required)>'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/migration.rb:415:in `migrate'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/migration.rb:433:in `up'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/migration.rb:433:in `new'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/migration.rb:486:in `initialize'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_specification.rb:89:in `connection'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_specification.rb:97:in `retrieve_connection'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:316:in `retrieve_connection'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:93:in `connection'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:185:in `checkout'
/Users/tamer/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:186:in `block in checkout'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:186:in `loop'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:190:in `block (2 levels) in checkout'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:236:in `checkout_new_connection'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:228:in `new_connection'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:25:in `postgresql_connection'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:25:in `new'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:228:in `initialize'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:939:in `connect'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:956:in `configure_connection'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:278:in `set_standard_conforming_strings'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:699:in `client_min_messages'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:483:in `query'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract_adapter.rb:195:in `log'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activesupport-3.0.3/lib/active_support/notifications/instrumenter.rb:21:in `instrument'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract_adapter.rb:197:in `block in log'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:487:in `block in query'
/Users/tamer/.rvm/gems/ruby-1.9.2-p290@my_app/gems/activerecord-3.0.3/lib/active_record/connection_adapters/postgresql_adapter.rb:487:in `exec'
-- C level backtrace information -------------------------------------------
[NOTE]
You may have encountered a bug in the Ruby interpreter or extension libraries.
Bug reports are welcome.
For details: http://www.ruby-lang.org/bugreport.html
Abort trap
我的 database.yml 文件是这样的
development:
encoding: unicode
adapter: postgresql
username: postgres
port: 5432
host: localhost
database: test
password: password
知道我做错了什么..这些是正确的凭据，因为我使用带有这些凭据的 GUI 工具连接到这个 postgres 数据库
我用了这个link安装 pg gem
最佳答案
鉴于您遇到了实际的段错误，我敢打赌您的 pg gem 与 libpg 有问题。您最近有没有升级您的操作系统？
如果这看起来合理，您可以尝试保存数据库的备份，破坏现有的 pg 安装(数据库、库和 gems)，然后重新安装它们以期消除导致问题的任何不兼容性.
关于ruby-on-rails - rake 数据库 :migrate not working on my postgres db，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/9261192/
我正在学习如何使用Nokogiri，根据这段代码我遇到了一些问题:require'rubygems'require'mechanize'post_agent=WWW::Mechanize.newpost_page=post_agent.get('http://www.vbulletin.org/forum/showthread.php?t=230708')puts"\nabsolutepathwithtbodygivesnil"putspost_page.parser.xpath('/html/body/div/div/div/div/div/table/tbody/tr/td/div
总的来说，我对ruby还比较陌生，我正在为我正在创建的对象编写一些rspec测试用例。许多测试用例都非常基础，我只是想确保正确填充和返回值。我想知道是否有办法使用循环结构来执行此操作。不必为我要测试的每个方法都设置一个assertEquals。例如:describeitem,"TestingtheItem"doit"willhaveanullvaluetostart"doitem=Item.new#HereIcoulddotheitem.name.shouldbe_nil#thenIcoulddoitem.category.shouldbe_nilendend但我想要一些方法来使用
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类classAprivatedeffooputs:fooendpublicdefbarputs:barendprivatedefzimputs:zimendprotecteddefdibputs:dibendendA的实例a=A.new测试a.foorescueputs:faila.barrescueputs:faila.zimrescueputs:faila.dibrescueputs:faila.gazrescueputs:fail测试输出failbarfailfailfail.发送测试[:foo,:bar,:zim,:dib,:gaz].each{|m|a.send(m)resc
很好奇，就使用rubyonrails自动化单元测试而言，你们正在做什么？您是否创建了一个脚本来在cron中运行rake作业并将结果邮寄给您？git中的预提交Hook？只是手动调用？我完全理解测试，但想知道在错误发生之前捕获错误的最佳实践是什么。让我们理所当然地认为测试本身是完美无缺的，并且可以正常工作。下一步是什么以确保他们在正确的时间将可能有害的结果传达给您？ 最佳答案 不确定您到底想听什么，但是有几个级别的自动代码库控制:在处理某项功能时，您可以使用类似autotest的内容获得关于哪些有效，哪些无效的即时反馈。要确保您的提
这似乎应该有一个直截了当的答案，但在Google上花了很多时间，所以我找不到它。这可能是缺少正确关键字的情况。在我的RoR应用程序中，我有几个模型共享一种特定类型的字符串属性，该属性具有特殊验证和其他功能。我能想到的最接近的类似示例是表示URL的字符串。这会导致模型中出现大量重复(甚至单元测试中会出现更多重复)，但我不确定如何让它更DRY。我能想到几个可能的方向...按照“validates_url_format_of”插件，但这只会让验证干给这个特殊的字符串它自己的模型，但这看起来很像重溶液为这个特殊的字符串创建一个ruby类，但是我如何得到ActiveRecord关联这个类模型
假设我做了一个模块如下:m=Module.newdoclassCendend三个问题:除了对m的引用之外，还有什么方法可以访问C和m中的其他内容？我可以在创建匿名模块后为其命名吗(就像我输入“module...”一样)？如何在使用完匿名模块后将其删除，使其定义的常量不再存在？ 最佳答案 三个答案:是的，使用ObjectSpace.此代码使c引用你的类(class)C不引用m:c=nilObjectSpace.each_object{|obj|c=objif(Class===objandobj.name=~/::C$/)}当然这取决于
我试图在一个项目中使用rake，如果我把所有东西都放到Rakefile中，它会很大并且很难读取/找到东西，所以我试着将每个命名空间放在lib/rake中它自己的文件中，我添加了这个到我的rake文件的顶部:Dir['#{File.dirname(__FILE__)}/lib/rake/*.rake'].map{|f|requiref}它加载文件没问题，但没有任务。我现在只有一个.rake文件作为测试，名为“servers.rake”，它看起来像这样:namespace:serverdotask:testdoputs"test"endend所以当我运行rakeserver:testid时
出于纯粹的兴趣，我很好奇如何按顺序创建PI，而不是在过程结果之后生成数字，而是让数字在过程本身生成时显示。如果是这种情况，那么数字可以自行产生，我可以对以前看到的数字实现垃圾收集，从而创建一个无限系列。结果只是在Pi系列之后每秒生成一个数字。这是我通过互联网筛选的结果:这是流行的计算机友好算法，类机器算法:defarccot(x,unity)xpow=unity/xn=1sign=1sum=0loopdoterm=xpow/nbreakifterm==0sum+=sign*(xpow/n)xpow/=x*xn+=2sign=-signendsumenddefcalc_pi(digits