I have a fairly repetitive use case of having to define attributes and
have them lock protected. I was thinking of defining a attr_accessor
kind of directive but one that creates a lock protected attribute -
class Module
def attr_sync_accessor(*symbols)
symbols.each do |symbol|
str = <<-EOF
def #{symbol}()
if @#{symbol}
@#{symbol}.synchronize { return @#{symbol} }
else
nil
end
end
EOF
module_eval(str)
str = <<-EOF
def #{symbol}=(val)
if @#{symbol}
@#{symbol}.synchronize { @#{symbol} = val }
else
@#{symbol} = val
@#{symbol}.extend(MonitorMixin)
end
end
EOF
module_eval(str)
end
end
end
···
#--------------
Now to use it you need to require monitor so
require 'monitor'
class A
attr_sync_accessor :hello
def get
hello
end
def set(val)
self.hello = val
end
end
irb(main):190:0* d = A.new
=> #<D:0x27f77d4>
irb(main):191:0> d.set "h"
=> "h"
irb(main):192:0> d.get
=> "h"
This works but obviously has some flaws, like for example first time
creation of attribute is unprotected as is the nil check, also it does
not address scope [private, protected etc.].
I am looking for suggestions on improvements to this if anyone else
also finds it useful or if it is solved by someone in some other way
and I have overlooked something.
TIA
- Nasir