[pmwiki-users] page text variable arithmetic

[blues]

hello.

i would like to perform some kind of arithmetic on
page text variables.

i am using pmform to add comments, and i would like
to have a way to know how many comments there are on
the page.

i was thinking to keep the value in a hidden PTV and
in the pmform template have a hidden input with the
count+1.

i thought that markup expressions would help me but
it looks like there is nothing similar (maybe a
{(eval "expression")} should be added).

any thoughts how i can achieve this?
instead to keep the value maybe there is a way to
dinamically count the number of comments?

blues