"H{ } substitute" is faster than "{ } substitute".

basis/colors/constants/constants.factor

@@ -9,7 +9,7 @@ IN: colors.constants
 : parse-color ( line -- name color )
     first4
     [ [ string>number 255 /f ] tri@ 1.0 <rgba> ] dip
-    [ blank? ] trim-head { { CHAR: \s CHAR: - } } substitute swap ;
+    [ blank? ] trim-head H{ { CHAR: \s CHAR: - } } substitute swap ;
 
 : parse-colors ( lines -- assoc )
     [ "!" head? not ] filter

basis/tools/test/test.factor

@@ -77,7 +77,8 @@ M: did-not-fail summary drop "Did not fail" ;
     [ { } quot with-datastack drop did-not-fail t ] [ drop f f ] recover ;
 
 : experiment-title ( word -- string )
-    "(" ?head drop ")" ?tail drop { { CHAR: - CHAR: \s } } substitute >title ;
+    "(" ?head drop ")" ?tail drop
+    H{ { CHAR: - CHAR: \s } } substitute >title ;
 
 MACRO: <experiment> ( word -- )
     [ stack-effect in>> length dup ]

basis/ui/text/pango/pango.factor

@@ -120,7 +120,7 @@ SYMBOL: dpi
 : escape-nulls ( str -- str' )
     #! Replace nulls with something else since Pango uses null-terminated
     #! strings
-    { { 0 CHAR: zero-width-no-break-space } } substitute ;
+    H{ { 0 CHAR: zero-width-no-break-space } } substitute ;
 
 : unpack-selection ( layout string/selection -- layout )
     dup selection? [

basis/ui/tools/listener/completion/completion.factor

@@ -17,7 +17,7 @@ SLOT: history
 
 : history-list ( interactor -- alist )
     history>> elements>>
-    [ dup string>> { { CHAR: \n CHAR: \s } } substitute ] { } map>assoc
+    [ dup string>> H{ { CHAR: \n CHAR: \s } } substitute ] { } map>assoc
     <reversed> ;
 
 : history-completions ( short interactor -- seq )

basis/unicode/data/data.factor

@@ -158,7 +158,7 @@ PRIVATE>
 
 : process-names ( data -- names-hash )
     1 swap (process-data) [
-        >lower { { CHAR: \s CHAR: - } } substitute swap
+        >lower H{ { CHAR: \s CHAR: - } } substitute swap
     ] H{ } assoc-map-as ;
 
 : multihex ( hexstring -- string )

core/vocabs/loader/loader.factor

@@ -42,7 +42,7 @@ M: string vocab-path ( string -- path/f )
 PRIVATE>
 
 : vocab-dir ( vocab -- dir )
-    vocab-name { { CHAR: . CHAR: / } } substitute ;
+    vocab-name H{ { CHAR: . CHAR: / } } substitute ;
 
 : append-vocab-dir ( vocab str/f -- path )
     [ vocab-name "." split ] dip

extra/mason/platform/platform.factor

@@ -5,7 +5,7 @@ mason.config bootstrap.image assocs ;
 IN: mason.platform
 
 : (platform) ( os cpu -- string )
-    { { CHAR: . CHAR: - } } substitute "-" glue ;
+    H{ { CHAR: . CHAR: - } } substitute "-" glue ;
 
 : platform ( -- string )
     target-os get name>> target-cpu get name>> (platform)

extra/svg/svg.factor

@@ -10,7 +10,7 @@ XML-NS: sodipodi-name http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd
 XML-NS: inkscape-name http://www.inkscape.org/namespaces/inkscape
 
 : svg-string>number ( string -- number )
-    { { CHAR: E CHAR: e } } substitute "e" split1
+    H{ { CHAR: E CHAR: e } } substitute "e" split1
     [ string>number ] [ [ string>number 10^ ] [ 1 ] if* ] bi* *
     >float ;
 

unmaintained/alien/cxx/cxx.factor

@@ -24,7 +24,7 @@ PRIVATE>
     add-mixin-instance define-class-tuple ;
 
 :: define-c++-method ( class-name generic name types effect virtual -- )
-    [ name % "_" % class-name { { CHAR: : CHAR: _ } } substitute % ] "" make           :> name'
+    [ name % "_" % class-name H{ { CHAR: : CHAR: _ } } substitute % ] "" make           :> name'
     effect [ in>> "self" suffix ] [ out>> ] bi <effect> :> effect'
     types class-name "*" append suffix                  :> types'
     effect in>> "," join                                :> args

unmaintained/alien/inline/types/types.factor

@@ -7,7 +7,7 @@ IN: alien.inline.types
 
 : cify-type ( str -- str' )
     dup word? [ name>> ] when
-    { { CHAR: - CHAR: space } } substitute ;
+    H{ { CHAR: - CHAR: space } } substitute ;
 
 : factorize-type ( str -- str' )
     cify-type

unmaintained/alien/marshall/structs/structs.factor

@@ -41,7 +41,7 @@ PRIVATE>
     name c-type fields>> [
         class swap
         {
-            [ name>> { { CHAR: space CHAR: - } } substitute ]
+            [ name>> H{ { CHAR: space CHAR: - } } substitute ]
             [ type>> ] [ reader>> ] [ writer>> ]
         } cleave define-struct-accessors
     ] each ;