Make gen-use-table.py py3 compatible (#932)

diff --git a/src/gen-use-table.py b/src/gen-use-table.py
index 0681725..ecbdfb9 100755
--- a/src/gen-use-table.py
+++ b/src/gen-use-table.py
@@ -1,9 +1,10 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
+from __future__ import print_function
 import sys
 
 if len (sys.argv) != 5:
-	print >>sys.stderr, "usage: ./gen-use-table.py IndicSyllabicCategory.txt IndicPositionalCategory.txt UnicodeData.txt Blocks.txt"
+	print ("usage: ./gen-use-table.py IndicSyllabicCategory.txt IndicPositionalCategory.txt UnicodeData.txt Blocks.txt", file=sys.stderr)
 	sys.exit (1)
 
 BLACKLISTED_BLOCKS = ["Thai", "Lao", "Tibetan"]
@@ -352,21 +353,21 @@
 defaults = ('O', 'No_Block')
 data = map_to_use(data)
 
-print "/* == Start of generated table == */"
-print "/*"
-print " * The following table is generated by running:"
-print " *"
-print " *   ./gen-use-table.py IndicSyllabicCategory.txt IndicPositionalCategory.txt UnicodeData.txt Blocks.txt"
-print " *"
-print " * on files with these headers:"
-print " *"
+print ("/* == Start of generated table == */")
+print ("/*")
+print (" * The following table is generated by running:")
+print (" *")
+print (" *   ./gen-use-table.py IndicSyllabicCategory.txt IndicPositionalCategory.txt UnicodeData.txt Blocks.txt")
+print (" *")
+print (" * on files with these headers:")
+print (" *")
 for h in headers:
 	for l in h:
-		print " * %s" % (l.strip())
-print " */"
-print
-print '#include "hb-ot-shape-complex-use-private.hh"'
-print
+		print (" * %s" % (l.strip()))
+print (" */")
+print ()
+print ('#include "hb-ot-shape-complex-use-private.hh"')
+print ()
 
 total = 0
 used = 0
@@ -374,22 +375,22 @@
 def print_block (block, start, end, data):
 	global total, used, last_block
 	if block and block != last_block:
-		print
-		print
-		print "  /* %s */" % block
+		print ()
+		print ()
+		print ("  /* %s */" % block)
 		if start % 16:
-			print ' ' * (20 + (start % 16 * 6)),
+			print (' ' * (20 + (start % 16 * 6)), end='')
 	num = 0
 	assert start % 8 == 0
 	assert (end+1) % 8 == 0
 	for u in range (start, end+1):
 		if u % 16 == 0:
-			print
-			print "  /* %04X */" % u,
+			print ()
+			print ("  /* %04X */" % u, end='')
 		if u in data:
 			num += 1
 		d = data.get (u, defaults)
-		sys.stdout.write ("%6s," % d[0])
+		print ("%6s," % d[0], end='')
 
 	total += end - start + 1
 	used += num
@@ -406,14 +407,14 @@
 ends = []
 for k,v in sorted(use_mapping.items()):
 	if k in use_positions and use_positions[k]: continue
-	print "#define %s	USE_%s	/* %s */" % (k, k, v.__name__[3:])
+	print ("#define %s	USE_%s	/* %s */" % (k, k, v.__name__[3:]))
 for k,v in sorted(use_positions.items()):
 	if not v: continue
 	for suf in v.keys():
 		tag = k + suf
-		print "#define %s	USE_%s" % (tag, tag)
-print ""
-print "static const USE_TABLE_ELEMENT_TYPE use_table[] = {"
+		print ("#define %s	USE_%s" % (tag, tag))
+print ("")
+print ("static const USE_TABLE_ELEMENT_TYPE use_table[] = {")
 for u in uu:
 	if u <= last:
 		continue
@@ -433,51 +434,51 @@
 			if last >= 0:
 				ends.append (last + 1)
 				offset += ends[-1] - starts[-1]
-			print
-			print
-			print "#define use_offset_0x%04xu %d" % (start, offset)
+			print ()
+			print ()
+			print ("#define use_offset_0x%04xu %d" % (start, offset))
 			starts.append (start)
 
 	print_block (block, start, end, data)
 	last = end
 ends.append (last + 1)
 offset += ends[-1] - starts[-1]
-print
-print
+print ()
+print ()
 occupancy = used * 100. / total
 page_bits = 12
-print "}; /* Table items: %d; occupancy: %d%% */" % (offset, occupancy)
-print
-print "USE_TABLE_ELEMENT_TYPE"
-print "hb_use_get_category (hb_codepoint_t u)"
-print "{"
-print "  switch (u >> %d)" % page_bits
-print "  {"
+print ("}; /* Table items: %d; occupancy: %d%% */" % (offset, occupancy))
+print ()
+print ("USE_TABLE_ELEMENT_TYPE")
+print ("hb_use_get_category (hb_codepoint_t u)")
+print ("{")
+print ("  switch (u >> %d)" % page_bits)
+print ("  {")
 pages = set([u>>page_bits for u in starts+ends])
 for p in sorted(pages):
-	print "    case 0x%0Xu:" % p
+	print ("    case 0x%0Xu:" % p)
 	for (start,end) in zip (starts, ends):
 		if p not in [start>>page_bits, end>>page_bits]: continue
 		offset = "use_offset_0x%04xu" % start
-		print "      if (hb_in_range<hb_codepoint_t> (u, 0x%04Xu, 0x%04Xu)) return use_table[u - 0x%04Xu + %s];" % (start, end-1, start, offset)
-	print "      break;"
-	print ""
-print "    default:"
-print "      break;"
-print "  }"
-print "  return USE_O;"
-print "}"
-print
+		print ("      if (hb_in_range<hb_codepoint_t> (u, 0x%04Xu, 0x%04Xu)) return use_table[u - 0x%04Xu + %s];" % (start, end-1, start, offset))
+	print ("      break;")
+	print ("")
+print ("    default:")
+print ("      break;")
+print ("  }")
+print ("  return USE_O;")
+print ("}")
+print ()
 for k in sorted(use_mapping.keys()):
 	if k in use_positions and use_positions[k]: continue
-	print "#undef %s" % k
+	print ("#undef %s" % k)
 for k,v in sorted(use_positions.items()):
 	if not v: continue
 	for suf in v.keys():
 		tag = k + suf
-		print "#undef %s" % tag
-print
-print "/* == End of generated table == */"
+		print ("#undef %s" % tag)
+print ()
+print ("/* == End of generated table == */")
 
 # Maintain at least 50% occupancy in the table */
 if occupancy < 50: