The line used to ignore the setup file for win32 is a regexp but it was after a "syntax: glob"
--- a/.hgignore
+++ b/.hgignore
@@ -13,7 +13,6 @@ tests/annotated
tests/*.err
build
dist
-Output/Mercurial-[0-9.]*.exe
doc/*.[0-9]
doc/*.[0-9].gendoc.txt
doc/*.[0-9].{x,ht}ml
@@ -23,3 +22,4 @@ mercurial/__version__.py
syntax: regexp
^\.pc/
+Output/Mercurial-[0-9.]*.exe