Convincing Programmers They Want To Use Lisp

Re:Convincing Programmers They Want To Use Lisp by CJefferson on Monday February 21, 2011 @04:10PM (#2247197)

This "thing that can't be done in any other language" looks an awful lot like RAII in C++.

For example I can write:

  {
    ifstream file("filename");
    ...
  } // file closed here automatically.

  {
    mutex_grab g(mutex);
    .....
  } // mutex automatically released here

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Re:Convincing Programmers They Want To Use Lisp by stcredzero on Monday February 21, 2011 @04:44PM (#2247338)

In Smalltalk, it's just a normal function you can add to Filename:

    doWithStreamThenClose: aBlock 
        | fileStream |
        fileStream := self newReadWriteStream.
        ^[aBlock value: fileStream]
            ensure: [fileStream close]

This allows one to do:

    (Filename named: 'mypath/foo.dat')
        doWithStreamThenClose: [ :fileStream |
             "do whatever you want with fileStream"
             "it shall be closed"
        ].

[ Parent | on HN ]