The agent runs all the commands in the block without allowing other agents using ask-concurrent to "interrupt". That is, other agents are put "on hold" and do not run any commands until the commands in the block are finished.
Note: This command is only useful in conjunction with ask-concurrent. In previous versions of NetLogo, this command was often needed, but in NetLogo 4.0, it is only ever needed if you are also using ask-concurrent.
See also ask-concurrent.
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