Index: Makefile
==================================================================
--- Makefile
+++ Makefile
@@ -1,9 +1,9 @@
 #!/usr/bin/make
 
 CC = gcc -Os -static
-TCLLIB = /home/drh/tcl/lib/libtcl8.6.a -lm -lz -lpthread -ldl
+TCLLIB = /home/drh/tcl/lib/libtcl8.7.a -lm -lz -lpthread -ldl
 TCLINC = /home/drh/tcl/include
 TCLSH = tclsh
 
 all: wapptclsh
 

Index: wapp.tcl
==================================================================
--- wapp.tcl
+++ wapp.tcl
@@ -73,24 +73,33 @@
 # In addition to the substitutions above, the text also does backslash
 # escapes.
 #
 proc wapp-subst {txt} {
   global wapp
-  regsub -all {%(html|url|qp|string|unsafe){1,1}?(|%)\((.+)\)\2} $txt \
-         {[wappInt-enc-\1 "\3"]} txt
-  dict append wapp .reply [uplevel 1 [list subst -novariables $txt]]
+  set txt [subst -novar -nocom $txt]
+  while {[regexp {^(.*?)%(html|url|qp|string|unsafe)(|%)\((.+?)\)\3(.*)$} \
+          $txt all before verb m1 arg after]} {
+    set arg [uplevel 1 [list subst $arg]]
+    dict append wapp .reply $before[wappInt-enc-$verb $arg]
+    set txt $after
+  }
+  dict append wapp .reply $txt
 }
 
 # Works like wapp-subst, but also removes whitespace from the beginning
 # of lines.
 #
 proc wapp-trim {txt} {
   global wapp
-  regsub -all {\n\s+} [string trim $txt] \n txt
-  regsub -all {%(html|url|qp|string|unsafe){1,1}?(|%)\((.+)\)\2} $txt \
-         {[wappInt-enc-\1 "\3"]} txt
-  dict append wapp .reply [uplevel 1 [list subst -novariables $txt]]
+  regsub -all {\n\s+} [subst -nocom -novar [string trim $txt]] \n txt
+  while {[regexp {^(.*?)%(html|url|qp|string|unsafe)(|%)\((.+?)\)\3(.*)$} \
+          $txt all before verb m1 arg after]} {
+    set arg [uplevel 1 [list subst $arg]]
+    dict append wapp .reply $before[wappInt-enc-$verb $arg]
+    set txt $after
+  }
+  dict append wapp .reply $txt
 }
 
 # There must be a wappInt-enc-NAME routine for each possible substitution
 # in wapp-subst.  Thus there are routines for "html", "url", "qp", and "unsafe".
 #