latex3
diff --git a/contrib/testfiles/chemformula001.luatex.tlg b/contrib/testfiles/chemformula001.luatex.tlg
@@ -13,7 +13,7 @@ Completed box being shipped out [1]
 ....\pdfcolorstack 0 pop
 ..\glue 25.0
 ..\glue(\lineskip) 0.0
-..\vbox(550.0+0.0)x345.0, glue set 525.89374fil, direction TLT
+..\vbox(550.0+0.0)x345.0, glue set 527.9436fil, direction TLT
 ...\write-{}
 ...\pdfcolorstack 0 push {0 g 0 G}
 ...\glue(\topskip) 3.16669
@@ -432,6 +432,7 @@ Completed box being shipped out [1]
 ....\penalty 10000
 ....\glue(\parfillskip) 0.0 plus 1.0fil
 ....\glue(\rightskip) 0.0
+...\glue -2.05006
 ...\glue 0.0 plus 1.0fil
 ...\glue 0.0
 ...\glue 0.0 plus 0.0001fil

diff --git a/contrib/testfiles/chemformula001.ptex.tlg b/contrib/testfiles/chemformula001.ptex.tlg
@@ -3,12 +3,24 @@ Don't change this file in any respect.
 Completed box being shipped out [1]
 \vbox(633.0+0.0)x407.0
 .\hbox(0.0+0.0)x0.0
-..\special{! /pgfH{/pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfshade \ETC.}
-..\special{! /pgfV{/pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfshade \ETC.}
-..\special{! /pgfA{ /pgfdiff 8 index round cvi 8 index round cvi sub 2 mul 1 add\ETC.}
-..\special{! /pgfR1{ newpath dup dup dup 0 360 arc clip newpath dup /pgfendx exc\ETC.}
-..\special{! /pgfR2{ newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc setrgb\ETC.}
-..\special{! /pgfR{ /pgfdiff 8 index round cvi 8 index round cvi sub 4 mul 1 add\ETC.}
+..\special{! /pgfHrgb{/pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfsha\ETC.}
+..\special{! /pgfVrgb{/pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfsha\ETC.}
+..\special{! /pgfArgb{ /pgfdiff 8 index round cvi 8 index round cvi sub 2 mul 1 \ETC.}
+..\special{! /pgfR1rgb{ newpath dup dup dup 0 360 arc clip newpath dup /pgfendx \ETC.}
+..\special{! /pgfR2rgb{ newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc set\ETC.}
+..\special{! /pgfRrgb{ /pgfdiff 8 index round cvi 8 index round cvi sub 4 mul 1 \ETC.}
+..\special{! /pgfHcmyk{ /pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfs\ETC.}
+..\special{! /pgfVcmyk{ /pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfs\ETC.}
+..\special{! /pgfAcmyk{ /pgfdiff 10 index round cvi 10 index round cvi sub 2 mul\ETC.}
+..\special{! /pgfR1cmyk{ newpath dup dup dup 0 360 arc clip newpath dup /pgfendx\ETC.}
+..\special{! /pgfR2cmyk{ newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc se\ETC.}
+..\special{! /pgfRcmyk{ /pgfdiff 10 index round cvi 10 index round cvi sub 4 mul\ETC.}
+..\special{! /pgfHgray{ /pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfs\ETC.}
+..\special{! /pgfVgray{ /pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfs\ETC.}
+..\special{! /pgfAgray{ /pgfdiff 4 index round cvi 4 index round cvi sub 2 mul 1\ETC.}
+..\special{! /pgfR1gray{ newpath dup dup dup 0 360 arc clip newpath dup /pgfendx\ETC.}
+..\special{! /pgfR2gray{ newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc se\ETC.}
+..\special{! /pgfRgray{ /pgfdiff 4 index round cvi 4 index round cvi sub 4 mul 1\ETC.}
 ..\special{!  /pgfsc{}bind def/pgffc{}bind def/pgfstr{stroke}bind def/pgffill{fi\ETC.}
 .\glue 16.0
 .\vbox(617.0+0.0)x345.0, shifted 62.0
@@ -20,7 +32,7 @@ Completed box being shipped out [1]
 ....\special{color pop}
 ..\glue 25.0
 ..\glue(\lineskip) 0.0
-..\vbox(550.0+0.0)x345.0, glue set 525.89377fil
+..\vbox(550.0+0.0)x345.0, glue set 527.9436fil
 ...\write-{}
 ...\special{color push gray 0}
 ...\special{! /pgf1{gsave exec 1.0 pgfw 2.00002 0.0 moveto -6.00006 4.00005 linet\ETC.}
@@ -431,6 +443,7 @@ Completed box being shipped out [1]
 ....\penalty 10000
 ....\glue(\parfillskip) 0.0 plus 1.0fil
 ....\glue(\rightskip) 0.0
+...\glue -2.05006
 ...\glue 0.0 plus 1.0fil
 ...\glue 0.0
 ...\glue 0.0 plus 0.0001fil

diff --git a/contrib/testfiles/chemformula001.tlg b/contrib/testfiles/chemformula001.tlg
@@ -13,7 +13,7 @@ Completed box being shipped out [1]
 ....\pdfcolorstack 0 pop
 ..\glue 25.0
 ..\glue(\lineskip) 0.0
-..\vbox(550.0+0.0)x345.0, glue set 525.89377fil
+..\vbox(550.0+0.0)x345.0, glue set 527.9436fil
 ...\write-{}
 ...\pdfcolorstack 0 push {0 g 0 G}
 ...\glue(\topskip) 3.16669
@@ -424,6 +424,7 @@ Completed box being shipped out [1]
 ....\penalty 10000
 ....\glue(\parfillskip) 0.0 plus 1.0fil
 ....\glue(\rightskip) 0.0
+...\glue -2.05006
 ...\glue 0.0 plus 1.0fil
 ...\glue 0.0
 ...\glue 0.0 plus 0.0001fil

diff --git a/contrib/testfiles/chemformula001.uptex.tlg b/contrib/testfiles/chemformula001.uptex.tlg
@@ -3,12 +3,24 @@ Don't change this file in any respect.
 Completed box being shipped out [1]
 \vbox(633.0+0.0)x407.0
 .\hbox(0.0+0.0)x0.0
-..\special{! /pgfH{/pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfshade \ETC.}
-..\special{! /pgfV{/pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfshade \ETC.}
-..\special{! /pgfA{ /pgfdiff 8 index round cvi 8 index round cvi sub 2 mul 1 add\ETC.}
-..\special{! /pgfR1{ newpath dup dup dup 0 360 arc clip newpath dup /pgfendx exc\ETC.}
-..\special{! /pgfR2{ newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc setrgb\ETC.}
-..\special{! /pgfR{ /pgfdiff 8 index round cvi 8 index round cvi sub 4 mul 1 add\ETC.}
+..\special{! /pgfHrgb{/pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfsha\ETC.}
+..\special{! /pgfVrgb{/pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfsha\ETC.}
+..\special{! /pgfArgb{ /pgfdiff 8 index round cvi 8 index round cvi sub 2 mul 1 \ETC.}
+..\special{! /pgfR1rgb{ newpath dup dup dup 0 360 arc clip newpath dup /pgfendx \ETC.}
+..\special{! /pgfR2rgb{ newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc set\ETC.}
+..\special{! /pgfRrgb{ /pgfdiff 8 index round cvi 8 index round cvi sub 4 mul 1 \ETC.}
+..\special{! /pgfHcmyk{ /pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfs\ETC.}
+..\special{! /pgfVcmyk{ /pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfs\ETC.}
+..\special{! /pgfAcmyk{ /pgfdiff 10 index round cvi 10 index round cvi sub 2 mul\ETC.}
+..\special{! /pgfR1cmyk{ newpath dup dup dup 0 360 arc clip newpath dup /pgfendx\ETC.}
+..\special{! /pgfR2cmyk{ newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc se\ETC.}
+..\special{! /pgfRcmyk{ /pgfdiff 10 index round cvi 10 index round cvi sub 4 mul\ETC.}
+..\special{! /pgfHgray{ /pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfs\ETC.}
+..\special{! /pgfVgray{ /pgfheight exch def 0.75 setlinewidth [] 0 setdash /pgfs\ETC.}
+..\special{! /pgfAgray{ /pgfdiff 4 index round cvi 4 index round cvi sub 2 mul 1\ETC.}
+..\special{! /pgfR1gray{ newpath dup dup dup 0 360 arc clip newpath dup /pgfendx\ETC.}
+..\special{! /pgfR2gray{ newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc se\ETC.}
+..\special{! /pgfRgray{ /pgfdiff 4 index round cvi 4 index round cvi sub 4 mul 1\ETC.}
 ..\special{!  /pgfsc{}bind def/pgffc{}bind def/pgfstr{stroke}bind def/pgffill{fi\ETC.}
 .\glue 16.0
 .\vbox(617.0+0.0)x345.0, shifted 62.0
@@ -20,7 +32,7 @@ Completed box being shipped out [1]
 ....\special{color pop}
 ..\glue 25.0
 ..\glue(\lineskip) 0.0
-..\vbox(550.0+0.0)x345.0, glue set 525.89377fil
+..\vbox(550.0+0.0)x345.0, glue set 527.9436fil
 ...\write-{}
 ...\special{color push gray 0}
 ...\special{! /pgf1{gsave exec 1.0 pgfw 2.00002 0.0 moveto -6.00006 4.00005 linet\ETC.}
@@ -431,6 +443,7 @@ Completed box being shipped out [1]
 ....\penalty 10000
 ....\glue(\parfillskip) 0.0 plus 1.0fil
 ....\glue(\rightskip) 0.0
+...\glue -2.05006
 ...\glue 0.0 plus 1.0fil
 ...\glue 0.0
 ...\glue 0.0 plus 0.0001fil

diff --git a/contrib/testfiles/chemformula001.xetex.tlg b/contrib/testfiles/chemformula001.xetex.tlg
@@ -16,7 +16,7 @@ Completed box being shipped out [1]
 ....\special{color pop}
 ..\glue 25.0
 ..\glue(\lineskip) 0.0
-..\vbox(550.0+0.0)x345.0, glue set 525.89377fil
+..\vbox(550.0+0.0)x345.0, glue set 527.9436fil
 ...\write-{}
 ...\special{color push gray 0}
 ...\glue(\topskip) 3.16669
@@ -459,6 +459,7 @@ Completed box being shipped out [1]
 ....\penalty 10000
 ....\glue(\parfillskip) 0.0 plus 1.0fil
 ....\glue(\rightskip) 0.0
+...\glue -2.05006
 ...\glue 0.0 plus 1.0fil
 ...\glue 0.0
 ...\glue 0.0 plus 0.0001fil

diff --git a/l3experimental/CHANGELOG.md b/l3experimental/CHANGELOG.md
@@ -7,6 +7,16 @@ this project uses date-based 'snapshot' version identifiers.
 
 ## [Unreleased]
 
+## [2019-05-28]
+
+### Added
+
+- New `l3graphics` module
+
+### Fixed
+
+- Missing `\scan_stop:` in benchmark code (fixes #577)
+
 ## [2019-05-03]
 
 ## Fixed
@@ -75,7 +85,8 @@ this project uses date-based 'snapshot' version identifiers.
 - New `l3color` module using `xcolor`-like expression syntax
 - New `l3draw` module, based on `pgf` layer of the TikZ system
 
-[Unreleased]: https://github.com/latex3/latex3/compare/2019-05-03...HEAD
+[Unreleased]: https://github.com/latex3/latex3/compare/2019-05-28...HEAD
+[2019-05-28]: https://github.com/latex3/latex3/compare/2019-05-03...2019-05-28
 [2019-05-03]: https://github.com/latex3/latex3/compare/2019-03-05...2019-05-03
 [2019-03-05]: https://github.com/latex3/latex3/compare/2019-01-28...2019-03-05
 [2019-01-28]: https://github.com/latex3/latex3/compare/2018-10-31...2019-01-28

diff --git a/l3experimental/README.md b/l3experimental/README.md
@@ -1,7 +1,7 @@
 Experimental LaTeX3 Concepts
 ============================
 
-Release 2019-05-03
+Release 2019-05-28
 
 Overview
 --------
@@ -25,11 +25,11 @@ bundles:
 * `l3cctab`
 * `l3color`
 * `l3draw`
+* `l3graphics`
 * `l3str`
 * `l3sys-shell`
 * `xcoffins`
 * `xgalley`
-* `xmarks`
 
 `l3benchmark`
 -------------
@@ -58,6 +58,12 @@ This module provides a code-level interface for constructing drawings. The
 interfaces are heavily inspired by the `pgf` layer of the widely-used
 TikZ system.
 
+`l3graphics`
+-------------
+
+This module provides interfaces for the inclusion of graphics files
+in documents, similar to the `graphics` package.
+
 `l3str`
 -------
 

diff --git a/l3experimental/l3benchmark/l3benchmark.dtx b/l3experimental/l3benchmark/l3benchmark.dtx
@@ -46,7 +46,7 @@
 %    }^^A
 % }
 %
-% \date{Released 2019-05-03}
+% \date{Released 2019-05-28}
 %
 % \maketitle
 %
@@ -66,8 +66,10 @@
 %     \cs{sys_timer:}
 %   \end{syntax}
 %   Expands to the current value of the engine's timer clock, a
-%   non-negative integer.  In engines without clock support this
-%   expands to $0$.
+%   non-negative integer.  In engines without clock support this expands
+%   to $0$ after an error.  In \LuaTeX{} only the CPU time is measured,
+%   while in other engines real time is measured (including time waiting
+%   for user input).
 % \end{function}
 %
 % \section{Benchmark}
@@ -128,7 +130,7 @@
 %
 %    \begin{macrocode}
 %<*package>
-\ProvidesExplPackage{l3benchmark}{2019-05-03}{}
+\ProvidesExplPackage{l3benchmark}{2019-05-28}{}
   {L3 Experimental benchmarking}
 %</package>
 %    \end{macrocode}
@@ -148,13 +150,13 @@
 \sys_if_engine_luatex:TF
   {
     \cs_new:Npn \sys_timer:
-      { \int_eval:w \lua_now:n { l3kernel.elapsedtime() } \scan_stop: }
+      { \lua_now:n { l3kernel.elapsedtime() } }
   }
   {
     \cs_if_exist:NT \tex_elapsedtime:D
       {
         \cs_new:Npn \sys_timer:
-          { \int_eval:w \tex_elapsedtime:D }
+          { \int_value:w \tex_elapsedtime:D }
       }
   }
 \@@_const:nn { sys_if_timer_exist }

diff --git a/l3experimental/l3cctab/l3cctab.dtx b/l3experimental/l3cctab/l3cctab.dtx
@@ -46,7 +46,7 @@
 %    }^^A
 % }
 %
-% \date{Released 2019-05-03}
+% \date{Released 2019-05-28}
 %
 % \maketitle
 %
@@ -150,7 +150,7 @@
 %
 %    \begin{macrocode}
 %<*package>
-\ProvidesExplPackage{l3cctab}{2019-05-03}{}
+\ProvidesExplPackage{l3cctab}{2019-05-28}{}
   {L3 Experimental category code tables}
 %</package>
 %    \end{macrocode}

diff --git a/l3experimental/l3color/l3color.dtx b/l3experimental/l3color/l3color.dtx
@@ -46,7 +46,7 @@
 %    }^^A
 % }
 %
-% \date{Released 2019-05-03}
+% \date{Released 2019-05-28}
 %
 % \maketitle
 %
@@ -265,7 +265,7 @@
 %
 %    \begin{macrocode}
 %<*package>
-\ProvidesExplPackage{l3color}{2019-05-03}{}
+\ProvidesExplPackage{l3color}{2019-05-28}{}
   {L3 Experimental color support}
 %</package>
 %    \end{macrocode}
@@ -292,9 +292,9 @@
 %
 % \subsection{Setup}
 %
-% \begin{variable}{\l_@@_tmp_tl}
+% \begin{variable}{\l_@@_internal_tl}
 %    \begin{macrocode}
-\tl_new:N \l_@@_tmp_tl
+\tl_new:N \l_@@_internal_tl
 %    \end{macrocode}
 % \end{variable}
 %
@@ -451,15 +451,7 @@
     \driver_color_pickup:N \l_@@_current_tl
     \tl_set_eq:cN { l_@@_named_ . _tl } \l_@@_current_tl
 %</package>
-    \group_begin:
-      \seq_map_inline:Nn \l_char_active_seq
-        {
-          \tl_set:Nx \l_@@_tmp_tl { \cs_to_str:N ##1 }
-          \char_set_active_eq:NN ##1 \l_@@_tmp_tl
-        }
-      \tl_set:Nx \l_@@_tmp_tl {#1}
-    \exp_args:NNV \group_end:
-    \@@_parse:nN \l_@@_tmp_tl #2
+    \exp_args:Ne \@@_parse:nN { \tl_to_str:n {#1} } #2
   }
 %    \end{macrocode}
 %   Before going to all of the effort of parsing an expression, these two
@@ -496,10 +488,10 @@
     \group_begin:
       \@@_extract:nNN {#2} \l_@@_model_tl \l_@@_value_tl
       \@@_parse_loop:w #3 ! ! ! ! \q_stop
-      \tl_set:Nx \l_@@_tmp_tl
+      \tl_set:Nx \l_@@_internal_tl
         { \l_@@_model_tl \c_space_tl \l_@@_value_tl }
     \exp_args:NNNV \group_end:
-    \tl_set:Nn #1 \l_@@_tmp_tl
+    \tl_set:Nn #1 \l_@@_internal_tl
   }
 %    \end{macrocode}
 %   This is the loop proper: there can be an open-ended set of colors to parse,
@@ -633,21 +625,42 @@
 % \end{macro}
 %
 % \begin{macro}[EXP]
-%   {\@@_parse_gray:w, \@@_parse_rgb:w, \@@_parse_cmyk:w, \@@_parse_spot:w}
+%   {
+%     \@@_parse_model_gray:w, \@@_parse_model_rgb:w,
+%     \@@_parse_model_cmyk:w, \@@_parse_model_spot:w
+%   }
+% \begin{macro}[EXP]{\@@_parse_number:n}
+% \begin{macro}[EXP]{\@@_parse_number:w}
 % \begin{macro}[EXP]{\@@_parse_spot_aux:w}
-%   Turn the input into internal form.
+%   Turn the input into internal form, also tidying up the number quickly.
 %    \begin{macrocode}
-\cs_new:Npn \@@_parse_gray:w #1 , #2 \q_stop {#1}
-\cs_new:Npn \@@_parse_rgb:w #1 , #2 , #3 , #4 \q_stop { #1 ~ #2 ~ #3 }
-\cs_new:Npn \@@_parse_cmyk:w #1 , #2 , #3 , #4 , #5 \q_stop
-  { #1 ~ #2 ~ #3 ~ #4 }
-\cs_new:Npn \@@_parse_spot:w #1 , #2 \q_stop
+\cs_new:Npn \@@_parse_model_gray:w #1 , #2 \q_stop { \@@_parse_number:n {#1} }
+\cs_new:Npn \@@_parse_model_rgb:w #1 , #2 , #3 , #4 \q_stop
+  {
+    \@@_parse_number:n {#1} ~ 
+    \@@_parse_number:n {#2} ~
+    \@@_parse_number:n {#3}
+  }
+\cs_new:Npn \@@_parse_model_cmyk:w #1 , #2 , #3 , #4 , #5 \q_stop
+  {
+    \@@_parse_number:n {#1} ~ 
+    \@@_parse_number:n {#2} ~
+    \@@_parse_number:n {#3} ~
+    \@@_parse_number:n {#4}
+  }
+\cs_new:Npn \@@_parse_model_spot:w #1 , #2 \q_stop
   { \@@_parse_spot_aux:w #1 ! 100 ! \q_stop }
 \cs_new:Npn \@@_parse_spot_aux:w #1 ! #2 ! #3 \q_stop
   { #1 ~ \fp_eval:n { #2 / 100 } }
+\cs_new:Npn \@@_parse_number:n #1
+  {  \@@_parse_number:w #1 . 0 . \q_stop }
+\cs_new:Npn \@@_parse_number:w #1 . #2 . #3 \q_stop
+  { \tl_if_blank:nTF {#1} { 0 } {#1} . #2 }
 %    \end{macrocode}
 % \end{macro}
 % \end{macro}
+% \end{macro}
+% \end{macro}
 %
 % \subsection{Selecting colors (and color models)}
 %
@@ -725,10 +738,10 @@
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_direct:nnN #1#2#3
   {
-    \cs_if_exist:cTF { @@_parse_ #1 :w }
+    \cs_if_exist:cTF { @@_parse_model_ #1 :w }
       {
         \tl_set:Nx #3
-          { #1 ~ \use:c {  @@_parse_ #1 :w } #2 , 0 , 0 , 0 , 0 \q_stop }
+          { #1 ~ \use:c {  @@_parse_model_ #1 :w } #2 , 0 , 0 , 0 , 0 \q_stop }
         \@@_check_model:N #3
       }
       {