Meta-TAB -> slime-complete-symbol
and
C-c M-i -> slime-fuzzy-complete-symbol
It can be found in the manual here:
http://common-lisp.net/project/slime/doc/html/Programming-He...
Also you can access documentation including the common lisp hyperspec:
http://common-lisp.net/project/slime/doc/html/Documentation....
It's an uphill battle to figure it out the first time but it gets easier.
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