我有以下数组:
@master = Array.new(4, Array.new(2, Array.new()))
=> [[[], []], [[], []], [[], []], [[], []]]
我正在尝试分配第一个最重要的值:
@master[0][0] = "x"
=> "x"
但这是一项多任务
@master
=> [["x", []], ["x", []], ["x", []], ["x", []]]
如何仅指定第一个值？我希望得到以下数组:
@master
=> [["x", []], [[], []], [[], []], [[], []]]
我正在尝试使用derailed_benchmarksgem 调试我的rails应用程序.我按照他们的Github上的说明进行操作.我可以在生产中本地运行我的服务器,但是当我尝试执行该命令时,derailed exec perf:mem_over_time我收到以下错误:
/gems/ruby-2.2.2/gems/derailed_benchmarks-1.1.3/lib/derailed_benchmarks/tasks.rb:92:in `call_app': Bad request: <html><body>You are being <a href="http://example.org/user_sessions/new">redirected</a>.</body></html> (RuntimeError)
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/derailed_benchmarks-1.1.3/lib/derailed_benchmarks/tasks.rb:145:in `block (2 levels) in <top (required)>'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/rake-10.3.2/lib/rake/task.rb:240:in `call'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/rake-10.3.2/lib/rake/task.rb:240:in `block in execute'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/rake-10.3.2/lib/rake/task.rb:235:in `each'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/rake-10.3.2/lib/rake/task.rb:235:in `execute'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/rake-10.3.2/lib/rake/task.rb:179:in `block in invoke_with_call_chain'
from /Users/cowan/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/monitor.rb:211:in `mon_synchronize'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/rake-10.3.2/lib/rake/task.rb:172:in `invoke_with_call_chain'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/rake-10.3.2/lib/rake/task.rb:165:in `invoke'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/derailed_benchmarks-1.1.3/bin/derailed:41:in `exec'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/thor-0.19.1/lib/thor/command.rb:27:in `run'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/thor-0.19.1/lib/thor/invocation.rb:126:in `invoke_command'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/thor-0.19.1/lib/thor.rb:359:in `dispatch'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/thor-0.19.1/lib/thor/base.rb:440:in `start'
from /Users/cowan/.rvm/gems/ruby-2.2.2/gems/derailed_benchmarks-1.1.3/bin/derailed:85:in `<top (required)>'
from /Users/cowan/.rvm/gems/ruby-2.2.2/bin/derailed:23:in `load'
from /Users/cowan/.rvm/gems/ruby-2.2.2/bin/derailed:23:in …我正在尝试将字符串与regexp匹配,但是当我认为它应该返回true时它返回false.
/^?+$/ =~ '???????????????' ? true : false
#irb example:
2.2.2 :001 > /^?+$/ =~ '?' ? true : false
=> false
我正在尝试编写一种方法，该方法接受未知数量的参数并对它们执行Hash＃dig。
def unknown_dig(hash, *args)
# do some magic?
hash.dig(non_array_args)
end
#example usage
unknown_dig(hash, 'a', 'b', 'c')
这可能吗？