Add sample for prime-symbol using groff

content/prime-symbol.md

@@ -1,7 +1,8 @@
 +++
 title = "The Prime Symbol"
 description = "In math mode, prime-time is always a good time."
-extra.typesetters = [ "typst", "sile", "xelatex" ]
+extra.typesetters = [ "typst", "sile", "xelatex", "groff" ]
+extra.typesetter_args = { groff = "-e -P-pA7" }
 +++
 
 Assorted ways of entering and rendering the troublesome prime symbol.

data/prime-symbol/groff.ms

@@ -0,0 +1,29 @@
+.nr HM .4cm
+.nr PO .4cm
+.nr LL 6.2cm
+.nr PI 0
+.nr PS 12p
+.nr VS 18p
+\# TODO convert OpenType fonts to something groff can use
+.fam P
+.LP
+Math mode manners:
+.LG
+.LG
+.EQ C
+f(x) mark = x sup 2 + 1
+.EN
+.LG
+.LG
+.EQ C
+f'(x) lineup = 2x
+.EN
+\# TODO complete prime input test with two fonts
+.LP
+Prose poses problems:
+.LP
+60*10'16"N 24*55'52"E (plain)
+.br
+60°10′16″N 24°55′52″E (unicode)
+.br
+60\[de]10\[fm]16\[sd]N 24\[de]55\[fm]52\[sd]E (native)