[PATCH 2/4] maint.mk: expand the prohibit_doubled_word regex

[Ján Tomko]

This check has a static list of words that are checked for repetitions.
Expand it before running the perl script to avoid using expensive
captures.
---
 ChangeLog    | 9 +++++++++
 top/maint.mk | 7 ++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 7dd78e3..b698a6c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 2016-07-26  Ján Tomko  <address@hidden>
 
+       maint.mk: expand the prohibit_doubled_word regex
+
+       This check has a static list of words that are checked for
+       repetitions.
+       Expand it before running the perl script to avoid using expensive
+       captures.
+
+2016-07-26  Ján Tomko  <address@hidden>
+
        maint.mk: speed up po_check
 
        There is some logic in sc_po_check that skips files based on their
diff --git a/top/maint.mk b/top/maint.mk
index a907bff..b074609 100644
--- a/top/maint.mk
+++ b/top/maint.mk
@@ -953,8 +953,13 @@ perl_filename_lineno_text_ =                               
                \
     -e '    print "$$ARGV:$$n:$$v\n";'                                 \
     -e '  }'
 
+prohibit_doubled_words_ = \
+    the then in an on if is it but for or at and do to
+# expand the regex before running the check to avoid using expensive captures
+prohibit_doubled_word_expanded_ = \
+    $(shell echo $(prohibit_doubled_words_) | sed -r 's/\b(\S+)\b/\1\\s\+\1/g')
 prohibit_doubled_word_RE_ ?= \
-  /\b(then?|[iao]n|i[fst]|but|f?or|at|and|[dt]o)\s+\1\b/gims
+    /\b(?:$(subst $(space),|,$(prohibit_doubled_word_expanded_)))\b/gims
 prohibit_doubled_word_ =                                               \
     -e 'while ($(prohibit_doubled_word_RE_))'                          \
     $(perl_filename_lineno_text_)
-- 
2.7.3