Test.hs

import Data.Tree
import Diagrams.Prelude
import Diagrams.TwoD.Layout.Tree
import Diagrams.Backend.SVG.CmdLine

t1 = Node 'A' [Node 'B' (map lf "CDE"), Node 'F' [Node 'G' (map lf "HIJ")]]
 where lf x = Node x []

exampleSymmTree :: Diagram B R2
exampleSymmTree = foldl1 (|||) (map renderWithSep [0.5..5])
 where renderWithSep sep = renderTree ((<> circle 1 # fc white) . text . (:[]))
                                      (~~)
                                      (symmLayout' (with & slHSep .~ sep & slVSep .~ sep) t1)
                                      # lw 0.03
                                      # centerXY # pad 1.1

main = mainWith exampleSymmTree

TestLabelBottom.hs

import Data.Tree
import Diagrams.Prelude
import Diagrams.TwoD.Layout.Tree
import Diagrams.Backend.SVG.CmdLine

t1 = Node 'A' [Node 'B' (map lf "CDE"), Node 'F' [Node 'G' (map lf "HIJ")]]
 where lf x = Node x []

exampleSymmTree :: Diagram B R2
exampleSymmTree = foldl1 (|||) (map renderWithSep [0.5..5])
 where renderWithSep sep = renderTree ((<> circle 1 # fc white) . text . (:[]))
                                      (~~)
                                      (symmLayout' (with & slHSep .~ sep & slVSep .~ sep) t1)
                                      # lw 0.03
                                      # centerXY # pad 1.1
                       === text (show sep) # scale 2

main = mainWith exampleSymmTree

TestLabelTop.hs

import Data.Tree
import Diagrams.Prelude
import Diagrams.TwoD.Layout.Tree
import Diagrams.Backend.SVG.CmdLine

t1 = Node 'A' [Node 'B' (map lf "CDE"), Node 'F' [Node 'G' (map lf "HIJ")]]
 where lf x = Node x []

exampleSymmTree :: Diagram B R2
exampleSymmTree = foldl1 (|||) (map renderWithSep [0.5..5])
 where renderWithSep sep = text (show sep) # scale 2
                       === renderTree ((<> circle 1 # fc white) . text . (:[]))
                                      (~~)
                                      (symmLayout' (with & slHSep .~ sep & slVSep .~ sep) t1)
                                      # lw 0.03
                                      # centerXY # pad 1.1

main = mainWith exampleSymmTree