regex - greedy block ()* contains wildcard -


i building grammar in antlr4, , getting warning

tl4.g4:224:12: greedy block ()* contains wildcard; non-greedy syntax ()*? may preferred

here line of code referring 

block     : ( statement | functiondecl )* (return expression ';')?     ;

what warning mean, how can correct ?

the warning telling block ()* greedy, meaning try match maximum occurrences of statement or functiondec1 which, depending on situation, might not expect.

changing ()*? makes non-greedy, suggested warning. means match minimum occurrences of statement or functiondec1.

expression examples strings:

samples:

foofoobar foobarbar foofoobarbarbar

expression:

(foo|bar)*bar

will give result:

foofoobar foobarbar foofoobarbarbar

expression:

(foo|bar)*?bar

will give result:

foofoobar foobar foofoobar

for last one, result stop @ first bar


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