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Message-ID: <CAPccJQHK-wQ6gYYtdq4gaGRXj2z9ROHWsw6w92Q7KG4MtHgHrA@mail.gmail.com>
Date: 2012-12-13T01:54:32Z
From: Asis Hallab
Subject: possible bug in function 'mclapply' of package parallel

Dear parallel users and developers,

I might have encountered a bug in the function 'mclapply' of package
'parallel'. I construct a matrix using the same input data and code with a
single difference: Once I use mclapply and the other time lapply.

Shockingly the result is NOT the same.

To evaluate please unpack the attached archive and execute
Rscript mclapply_test.R

I put the two simple functions I wrote inside the R script and the
serialized input matrix.
My function is once executed using mclapply and the other time lapply
internally. - There's an argument lapply.funk, one can set to mclapply.

The results are checked for identity with a striking FALSE.

Any hints on my misuse and or misunderstanding of mclapply or verification
of a true bug will be much appreciated.

Kind regards!