Problem Analysis Once you have done a sparse or greedy count, all your following counts will also be sparse or greedy - this is a well documented bug in Tcl 8.4!

Reminder ...
.* is a greedy match - any character and AS MANY AS POSSIBLE
.*? is a sparse match - any character but AS FEW AS POSSIBLE

set demo abc@def@ghi@jkl
#
# Correctly working greedy matches
regexp (.*)@(.*) $demo all first second
puts "$first and $second"
#
# Correctly working sparse matches
regexp (.*?)@(.*?) $demo all first second
puts "$first and $second"
#
# Both matches will be SPARSE here
regexp (.*?)@(.*) $demo all first second
puts "$first and $second"
#
# Both matches will be GREEDY here
regexp (.*)@(.*?) $demo all first second
puts "$first and $second"

Running that, we get:

earth-wind-and-fire:~/oct07/camb grahamellis$ tclsh spag
abc@def@ghi and jkl
abc and
abc and
abc@def@ghi and jkl
earth-wind-and-fire:~/oct07/camb grahamellis$

Suggested Work-around

You can emulate a sparse match by excluding the delimiter character from he group that you would be sparse matching, and using a greedy match.

Thus
regexp (.*?)@(.*) $demo all first second
can be rewritten as
regexp {([^@]*)@(.*)} $demo all first second
if you really needed sparse followed by greedy!

result:
abc and def@ghi@jkl
(written 2007-10-27 07:09:34)

 T247 - Tcl/Tk - Advanced Regular Expressions

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Better technology makes for longer commutes?
What we teach - expained for the non-technical
The little gestures that can really count
Sparse and Greedy matching - Tcl 8.4
Buffering of inputs to expect, and match order
Tcl / regsub - changing a string and using interesting bits
What is Expect?
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