Ruby Study Notes (7)-closures

An important feature of closures is that variables defined inside a process (method) can be referenced even after the method call is complete! (That is, the lifecycle is extended)

Def method (n) puts "n = # {n}"; # Return proc {| I | n + = I} # key: Proc is a process object, it can only be called by "delegate". Here, the Parameter Variable N is referenced in the process. After multiple calls, N references are retained to form a closure! Endadelegate = method (0); # it can be understood as a delegate in C #. At the same time, this statement initializes n to 0 puts adelegate. call (1); # n = 0 after the last line is run, and then input parameter 1, equivalent to N = n + 1, that is, the final n = 1 puts adelegate. call (5); # Similarly, n = 6 puts adelegate. call (10); # N = 16