Concurrent ML (CML) is a concurrent extension of the Standard ML programming language.
Here is sample code to print "hello, world" to the console. It spawns a thread which creates a channel for strings. This thread then spawns another thread which prints the first string that is received on the channel. The former thread then sends the "hello, world\n" string on the channel. It uses SML/NJ and CML (note that the heap name will be different on non linux-x86 platforms; you may need to change the line with "cml_test.x86-linux" to something different):