From b9b20733761857fab6619a82c5854278231c1523 Mon Sep 17 00:00:00 2001
From: Brent Yorgey <byorgey@gmail.com>
Date: Thu, 5 Jun 2014 13:40:31 -0400
Subject: [PATCH] add convenience synonyms [hv]sep for [hv]cat' (with & sep .~
 x)

---
 src/Diagrams/TwoD.hs             |  4 ++--
 src/Diagrams/TwoD/Combinators.hs | 25 ++++++++++++++++++++-----
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/src/Diagrams/TwoD.hs b/src/Diagrams/TwoD.hs
index c899512c..69cd39ec 100644
--- a/src/Diagrams/TwoD.hs
+++ b/src/Diagrams/TwoD.hs
@@ -201,8 +201,8 @@ module Diagrams.TwoD
          -- * Combinators
          -- ** Combining multiple diagrams
        , (===), (|||), atAngle
-       , hcat, hcat'
-       , vcat, vcat'
+       , hcat, hcat', hsep
+       , vcat, vcat', vsep
 
          -- ** Spacing and envelopes
        , strutX, strutY
diff --git a/src/Diagrams/TwoD/Combinators.hs b/src/Diagrams/TwoD/Combinators.hs
index 775d6dc8..ef0ee07a 100644
--- a/src/Diagrams/TwoD/Combinators.hs
+++ b/src/Diagrams/TwoD/Combinators.hs
@@ -21,8 +21,8 @@ module Diagrams.TwoD.Combinators
       (===), (|||), atAngle
 
       -- * n-ary combinators
-    , hcat, hcat'
-    , vcat, vcat'
+    , hcat, hcat', hsep
+    , vcat, vcat', vsep
 
       -- * Spacing/envelopes
     , strutR2
@@ -37,6 +37,7 @@ module Diagrams.TwoD.Combinators
 
     ) where
 
+import           Control.Lens ((&), (.~))
 import           Data.AffineSpace
 import           Data.Colour
 import           Data.Default.Class
@@ -116,11 +117,18 @@ hcat = hcat' def
 
 -- | A variant of 'hcat' taking an extra 'CatOpts' record to control
 --   the spacing.  See the 'cat'' documentation for a description of
---   the possibilities.
+--   the possibilities. For the common case of setting just a
+--   separation amount, see 'hsep'.
 hcat' :: (Juxtaposable a, HasOrigin a, Monoid' a, V a ~ R2)
       => CatOpts R2 -> [a] -> a
 hcat' = cat' unitX
 
+-- | A convenient synonym for horizontal concatenation with
+--   separation: @hsep s === hcat' (with & sep .~ s)@.
+hsep :: (Juxtaposable a, HasOrigin a, Monoid' a, V a ~ R2)
+     => Scalar R2 -> [a] -> a
+hsep s = hcat' (def & sep .~ s)
+
 -- | Lay out a list of juxtaposable objects in a column from top to
 --   bottom, so that their local origins lie along a single vertical
 --   line, with successive envelopes tangent to one another.
@@ -137,12 +145,19 @@ vcat :: (Juxtaposable a, HasOrigin a, Monoid' a, V a ~ R2)
 vcat = vcat' def
 
 -- | A variant of 'vcat' taking an extra 'CatOpts' record to control
---   the spacing.  See the 'cat'' documentation for a description of the
---   possibilities.
+--   the spacing.  See the 'cat'' documentation for a description of
+--   the possibilities.  For the common case of setting just a
+--   separation amount, see 'vsep'.
 vcat' :: (Juxtaposable a, HasOrigin a, Monoid' a, V a ~ R2)
       => CatOpts R2 -> [a] -> a
 vcat' = cat' (negateV unitY)
 
+-- | A convenient synonym for vertical concatenation with
+--   separation: @vsep s === vcat' (with & sep .~ s)@.
+vsep :: (Juxtaposable a, HasOrigin a, Monoid' a, V a ~ R2)
+     => Scalar R2 -> [a] -> a
+vsep s = vcat' (def & sep .~ s)
+
 -- | @strutR2 v@ is a two-dimensional diagram which produces no
 --   output, but with respect to alignment, envelope, /and trace/ acts
 --   like a 1-dimensional segment oriented along the vector @v@, with