to be continued!
Word splitting occurs once any of the following expansions are done (and only then!)
Bash will scan the results of these expansions for special
IFS characters that mark word boundaries. This is only done on results that are not double-quoted!
Internal Field Separator IFS
IFS variable holds the characters that Bash sees as word boundaries in this step. The default contains the characters
These characters are also assumed when IFS is unset. When
IFS is empty (nullstring), no word splitting is performed at all.
The results of the expansions mentioned above are scanned for
IFS-characters. If one or more (in a sequence) of them is found, the expansion result is split at these positions into multiple words.
This doesn't happen when the expansion results were double-quoted.
When a null-string (e.g., something that before expanded to »nothing«) is found, it is removed, unless it is quoted (
Again note: Without any expansion beforehand, Bash won't perform word splitting! In this case, the initial token parsing is solely responsible.