diff --git a/runtime/syntax/testdir/dumps/vim_expr_00.dump b/runtime/syntax/testdir/dumps/vim_expr_00.dump
index 91ae939..dd1cfa7 100644
--- a/runtime/syntax/testdir/dumps/vim_expr_00.dump
+++ b/runtime/syntax/testdir/dumps/vim_expr_00.dump
@@ -17,4 +17,4 @@
 |e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|\|3|1|6| |\|3|1| |\|3| |\|x|1|f| |\|x|f| |\|X|1|F| |\|X|F| |\|u|0|2|a|4| |\|U|0@4|2|a|4| |\|b| |\|e| |\|f| |\|n| |\|r| |\|t| |\@1
 | |\|"| |\|<|C|-|W|>|'| +0#0000000&@63
 |e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|\+0#e000e06&|3|1|6|0+0#e000002&| |-| |\+0#e000e06&|x|1|f|0+0#e000002&| |-| |\+0#e000e06&|X|1|F|0+0#e000002&| |-| |\+0#e000e06&|u|0|2|a|4|0+0#e000002&| |-| |\+0#e000e06&|U|0@4|2|a|4|0+0#e000002&|"| +0#0000000&@21
-|"|i|n|p|u|t|/|v|i|m|_|e|x|p|r|.|v|i|m|"| |3|2|L|,| |1@1|6|3|B| @25|1|,|1| @10|T|o|p| 
+|"|i|n|p|u|t|/|v|i|m|_|e|x|p|r|.|v|i|m|"| |3|1|L|,| |1@1|6|2|B| @25|1|,|1| @10|T|o|p| 
diff --git a/runtime/syntax/testdir/dumps/vim_expr_01.dump b/runtime/syntax/testdir/dumps/vim_expr_01.dump
index 5f9b02e..c7d4ed8 100644
--- a/runtime/syntax/testdir/dumps/vim_expr_01.dump
+++ b/runtime/syntax/testdir/dumps/vim_expr_01.dump
@@ -13,8 +13,8 @@
 @75
 |e+0#af5f00255&|c|h|o| +0#0000000&|'+0#e000002&|D|o|n|'@1|t| |h|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:| |{@1| |{|1| |+| |2|}| |}@1|'| +0#0000000&@22
 |e+0#af5f00255&|c|h|o| +0#0000000&|"+0#e000002&|D|o|n|'|t| |h|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:| |{@1| |{|1| |+| |2|}| |}@1|"| +0#0000000&@23
-|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\|t|{+0#e000e06&@1| +0#e000002&|{+0#0000000&| |s+0#00e0e07&|t|r|i|n|g|(+0#e000e06&|{|'+0#e000002&|f|o@1|'|:+0#0000000&| |'+0#e000002&|b|a|r|'|}+0#e000e06&|)| +0#0000000&|}| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&@8
-|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\|t|{+0#e000e06&@1| +0#e000002&|{+0#0000000&| |$+0#e000002&|'|n|e|s|t|e|d|:| |{+0#e000e06&@1| +0#e000002&|{+0#0000000&|1| |++0#af5f00255&| +0#0000000&|2|}| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&|}| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&@6
-|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\+0#e000e06&|t|{@1| +0#e000002&|{+0#0000000&| |s+0#00e0e07&|t|r|i|n|g|(+0#e000e06&|{|"+0#e000002&|f|o@1|"|:+0#0000000&| |"+0#e000002&|b|a|r|"|}+0#e000e06&|)| +0#0000000&|}| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&@8
-|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\+0#e000e06&|t|{@1| +0#e000002&|{+0#0000000&| |$+0#e000002&|"|n|e|s|t|e|d|:| |{+0#e000e06&@1| +0#e000002&|{+0#0000000&|1| |++0#af5f00255&| +0#0000000&|2|}| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&|}| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&@6
-@57|1|9|,|1| @9|9|2|%| 
+|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\|t|{+0#e000e06&@1| +0#e000002&|{+0#e000e06&| +0#0000000&|s+0#00e0e07&|t|r|i|n|g|(+0#e000e06&|{|'+0#e000002&|f|o@1|'|:+0#0000000&| |'+0#e000002&|b|a|r|'|}+0#e000e06&|)| +0#0000000&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&@8
+|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\|t|{+0#e000e06&@1| +0#e000002&|{+0#e000e06&| +0#0000000&|$+0#e000002&|'|n|e|s|t|e|d|:| |{+0#e000e06&@1| +0#e000002&|{+0#e000e06&|1+0#e000002&| +0#0000000&|++0#af5f00255&| +0#0000000&|2+0#e000002&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&@6
+|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\+0#e000e06&|t|{@1| +0#e000002&|{+0#e000e06&| +0#0000000&|s+0#00e0e07&|t|r|i|n|g|(+0#e000e06&|{|"+0#e000002&|f|o@1|"|:+0#0000000&| |"+0#e000002&|b|a|r|"|}+0#e000e06&|)| +0#0000000&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&@8
+|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\+0#e000e06&|t|{@1| +0#e000002&|{+0#e000e06&| +0#0000000&|$+0#e000002&|"|n|e|s|t|e|d|:| |{+0#e000e06&@1| +0#e000002&|{+0#e000e06&|1+0#e000002&| +0#0000000&|++0#af5f00255&| +0#0000000&|2+0#e000002&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&@6
+@57|1|9|,|1| @9|B|o|t| 
diff --git a/runtime/syntax/testdir/dumps/vim_expr_99.dump b/runtime/syntax/testdir/dumps/vim_expr_99.dump
index 4bcf10a..b59cdc6 100644
--- a/runtime/syntax/testdir/dumps/vim_expr_99.dump
+++ b/runtime/syntax/testdir/dumps/vim_expr_99.dump
@@ -1,4 +1,6 @@
-|e+0#af5f00255#ffffff0|c|h|o| +0#0000000&|$+0#e000002&|"|\+0#e000e06&|3|1|6|0+0#e000002&| |-| |\+0#e000e06&|x|1|f|0+0#e000002&| |-| |\+0#e000e06&|X|1|F|0+0#e000002&| |-| |\+0#e000e06&|u|0|2|a|4|0+0#e000002&| |-| |\+0#e000e06&|U|0@4|2|a|4|0+0#e000002&|"| +0#0000000&@21
+|e+0#af5f00255#ffffff0|c|h|o| +0#0000000&|$+0#e000002&|'|\|3|1|6| |\|3|1| |\|3| |\|x|1|f| |\|x|f| |\|X|1|F| |\|X|F| |\|u|0|2|a|4| |\|U|0@4|2|a|4| |\|b| |\|e| |\|f| |\|n| |\|r| |\|t| |\@1
+| |\|"| |\|<|C|-|W|>|'| +0#0000000&@63
+|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|\+0#e000e06&|3|1|6|0+0#e000002&| |-| |\+0#e000e06&|x|1|f|0+0#e000002&| |-| |\+0#e000e06&|X|1|F|0+0#e000002&| |-| |\+0#e000e06&|u|0|2|a|4|0+0#e000002&| |-| |\+0#e000e06&|U|0@4|2|a|4|0+0#e000002&|"| +0#0000000&@21
 @75
 |e+0#af5f00255&|c|h|o| +0#0000000&|"+0#e000002&|\+0#e000e06&|<|C|-|a|>|"+0#e000002&| +0#0000000&@61
 |e+0#af5f00255&|c|h|o| +0#0000000&|"+0#e000002&|\+0#e000e06&|<|*|C|-|a|>|"+0#e000002&| +0#0000000&@60
@@ -11,10 +13,8 @@
 @75
 |e+0#af5f00255&|c|h|o| +0#0000000&|'+0#e000002&|D|o|n|'@1|t| |h|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:| |{@1| |{|1| |+| |2|}| |}@1|'| +0#0000000&@22
 |e+0#af5f00255&|c|h|o| +0#0000000&|"+0#e000002&|D|o|n|'|t| |h|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:| |{@1| |{|1| |+| |2|}| |}@1|"| +0#0000000&@23
-|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\|t|{+0#e000e06&@1| +0#e000002&|{+0#0000000&| |s+0#00e0e07&|t|r|i|n|g|(+0#e000e06&|{|'+0#e000002&|f|o@1|'|:+0#0000000&| |'+0#e000002&|b|a|r|'|}+0#e000e06&|)| +0#0000000&|}| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&@8
-|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\|t|{+0#e000e06&@1| +0#e000002&|{+0#0000000&| |$+0#e000002&|'|n|e|s|t|e|d|:| |{+0#e000e06&@1| +0#e000002&|{+0#0000000&|1| |++0#af5f00255&| +0#0000000&|2|}| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&|}| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&@6
-|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\+0#e000e06&|t|{@1| +0#e000002&|{+0#0000000&| |s+0#00e0e07&|t|r|i|n|g|(+0#e000e06&|{|"+0#e000002&|f|o@1|"|:+0#0000000&| |"+0#e000002&|b|a|r|"|}+0#e000e06&|)| +0#0000000&|}| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&@8
-|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\+0#e000e06&|t|{@1| +0#e000002&|{+0#0000000&| |$+0#e000002&|"|n|e|s|t|e|d|:| |{+0#e000e06&@1| +0#e000002&|{+0#0000000&|1| |++0#af5f00255&| +0#0000000&|2|}| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&|}| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&@6
-> @74
-|~+0#4040ff13&| @73
-| +0#0000000&@56|3|2|,|0|-|1| @7|B|o|t| 
+|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\|t|{+0#e000e06&@1| +0#e000002&|{+0#e000e06&| +0#0000000&|s+0#00e0e07&|t|r|i|n|g|(+0#e000e06&|{|'+0#e000002&|f|o@1|'|:+0#0000000&| |'+0#e000002&|b|a|r|'|}+0#e000e06&|)| +0#0000000&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&@8
+|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|'|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\|t|{+0#e000e06&@1| +0#e000002&|{+0#e000e06&| +0#0000000&|$+0#e000002&|'|n|e|s|t|e|d|:| |{+0#e000e06&@1| +0#e000002&|{+0#e000e06&|1+0#e000002&| +0#0000000&|++0#af5f00255&| +0#0000000&|2+0#e000002&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|'+0#e000002&| +0#0000000&@6
+|e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\+0#e000e06&|t|{@1| +0#e000002&|{+0#e000e06&| +0#0000000&|s+0#00e0e07&|t|r|i|n|g|(+0#e000e06&|{|"+0#e000002&|f|o@1|"|:+0#0000000&| |"+0#e000002&|b|a|r|"|}+0#e000e06&|)| +0#0000000&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&@8
+>e+0#af5f00255&|c|h|o| +0#0000000&|$+0#e000002&|"|H|i|g|h|l|i|g|h|t| |i|n|t|e|r|p|o|l|a|t|i|o|n|:|\+0#e000e06&|t|{@1| +0#e000002&|{+0#e000e06&| +0#0000000&|$+0#e000002&|"|n|e|s|t|e|d|:| |{+0#e000e06&@1| +0#e000002&|{+0#e000e06&|1+0#e000002&| +0#0000000&|++0#af5f00255&| +0#0000000&|2+0#e000002&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&|}+0#e000e06&| +0#e000002&|}+0#e000e06&@1|"+0#e000002&| +0#0000000&@6
+@57|3|1|,|1| @9|B|o|t| 
diff --git a/runtime/syntax/testdir/input/vim_expr.vim b/runtime/syntax/testdir/input/vim_expr.vim
index be2cb2c..439c1b6 100644
--- a/runtime/syntax/testdir/input/vim_expr.vim
+++ b/runtime/syntax/testdir/input/vim_expr.vim
@@ -29,4 +29,3 @@
 echo $'Highlight interpolation:\t{{ { $'nested: {{ {1 + 2} }}' } }}'
 echo $"Highlight interpolation:\t{{ { string({"foo": "bar"}) } }}"
 echo $"Highlight interpolation:\t{{ { $"nested: {{ {1 + 2} }}" } }}"
-
diff --git a/runtime/syntax/vim.vim b/runtime/syntax/vim.vim
index 2179953..e9feb35 100644
--- a/runtime/syntax/vim.vim
+++ b/runtime/syntax/vim.vim
@@ -377,7 +377,7 @@
 
 syn region	vimString start=+$'+ end=+'+ skip=+''+ oneline contains=vimStringInterpolationBrace,vimStringInterpolationExpr
 syn region	vimString start=+$"+ end=+"+ oneline contains=@vimStringGroup,vimStringInterpolationBrace,vimStringInterpolationExpr
-syn region	vimStringInterpolationExpr matchgroup=vimOperParen start=+{+ end=+}+ oneline contains=vimFunc,vimFuncVar,vimOper,vimNotation,vimOperParen,vimString,vimVar
+syn region	vimStringInterpolationExpr matchgroup=vimSep start=+{+ end=+}+ oneline contains=vimFunc,vimFuncVar,vimOper,vimOperParen,vimNotation,vimNumber,vimString,vimVar
 syn match	vimStringInterpolationBrace "{{"
 syn match	vimStringInterpolationBrace "}}"