They don’t have to be glorified for loops, even if they usually are. Map and Filter should be capable of running in parallel or asynchronously, and some languages provide this.
And many languages, have parallel for constructs. The openmp #pragma parallel extensions in C/C++ for example. Of course its possible to create constructs which provide the messages passing for clustered environments too.
And maybe that is part of the problem with a generic 'map' your not really sure the underlying implementation, is it parallel, clustered, serial, etc? So you end up with map(), parallel_map(), mpi_map(), etc, and how to you control the parallelism. Do you just let it default or do you have levers to control the batch & interleave. Pretty soon, its not such a simple construct anymore.
And maybe that is part of the problem with a generic 'map' your not really sure the underlying implementation, is it parallel, clustered, serial, etc? So you end up with map(), parallel_map(), mpi_map(), etc, and how to you control the parallelism. Do you just let it default or do you have levers to control the batch & interleave. Pretty soon, its not such a simple construct anymore.