regex - Look-ahead and look-behind assertions with regexprep -

the following works expected perl's s///g string replacement operator:

  db<18> $s = 'camelcasetext.ext'   db<19> $s =~ s/\w|(?<=[^\wa-z_])(?=[a-z])/\$/g; print $s camel$case$text$ext

...but fails in matlab:

>> regexprep('camelcasetext.ext', '\w|(?<=[^\wa-z_])(?=[a-z])', '$')  ans =  camelcasetext$ext

how can 1 achieve effect illustrated perl example using matlab?

i think need specify emptymatch option. according the docs, ignores zero-length matches default.

>> regexprep('camelcasetext.ext', '\w|(?<=[^\wa-z_])(?=[a-z])', '$', 'emptymatch')

DIs