Minimal support for SIRange in LaTeX reader (#6418)

Add support for `\SIRange{firstnumber}{secondnumber}{unit}` provided by siunitx.

An en-dash is used instead of localized "to".

src/Text/Pandoc/Readers/LaTeX.hs

@@ -259,6 +259,29 @@ dosiunitx = do
                       emptyOr160 unit,
                       unit]
 
+-- converts e.g. \SIRange{100}{200}{\ms} to "100 ms--200 ms"
+doSIRange :: PandocMonad m => LP m Inlines
+doSIRange = do
+  skipopts
+  startvalue <- tok
+  startvalueprefix <- option "" $ bracketed tok
+  stopvalue <- tok
+  stopvalueprefix <- option "" $ bracketed tok
+  unit <- grouped (mconcat <$> many1 siUnit) <|> siUnit <|> tok
+  let emptyOr160 "" = ""
+      emptyOr160 _  = "\160"
+  return . mconcat $ [startvalueprefix,
+                      emptyOr160 startvalueprefix,
+                      startvalue,
+                      emptyOr160 unit,
+                      unit,
+                      "\8211", -- An en-dash
+                      stopvalueprefix,
+                      emptyOr160 stopvalueprefix,
+                      stopvalue,
+                      emptyOr160 unit,
+                      unit]
+
 siUnit :: PandocMonad m => LP m Inlines
 siUnit = do
   Tok _ (CtrlSeq name) _ <- anyControlSeq
@@ -1075,6 +1098,7 @@ inlineCommands = M.union inlineLanguageCommands $ M.fromList
   , ("acsp", doAcronymPlural "abbrv")
   -- siuntix
   , ("SI", dosiunitx)
+  , ("SIRange", doSIRange)
   -- hyphenat
   , ("bshyp", lit "\\\173")
   , ("fshyp", lit "/\173")

test/command/3587.md

@@ -55,3 +55,62 @@
 [Para [Str "18.2\160\176C"]]
 ```
 
+# SIRange tests
+
+## Integer range with simple common units
+
+```
+% pandoc -f latex -t native
+\SIRange{10}{20}{\gram}
+^D
+[Para [Str "10\160g\8211\&20\160g"]]
+```
+```
+% pandoc -f latex -t native
+\SIRange{35}{9}{\milli\meter}
+^D
+[Para [Str "35\160mm\8211\&9\160mm"]]
+```
+```
+% pandoc -f latex -t native
+\SIRange{4}{97367265}{\celsius}
+^D
+[Para [Str "4\160\176C\8211\&97367265\160\176C"]]
+```
+
+## Decimal range with simple units
+
+```
+% pandoc -f latex -t native
+\SIRange{4.5}{97367265.5}{\celsius}
+^D
+[Para [Str "4.5\160\176C\8211\&97367265.5\160\176C"]]
+```
+
+## Squared units
+
+```
+% pandoc -f latex -t native
+\SIRange{10}{20}{\square\meter}
+^D
+[Para [Str "10\160m\178\8211\&20\160m\178"]]
+```
+
+## Ignore round precision
+
+`round-precision` option appears to be ignored by `\SI` as of 7c6dbd37e, so
+`\SIRange` will ignore it as well.
+
+```
+% pandoc -f latex -t native
+\SIRange[round-precision=2]{10}{20}{\gram}
+^D
+[Para [Str "10\160g\8211\&20\160g"]]
+```
+```
+% pandoc -f latex -t native
+\SIRange[round-precision=2]{10.0}{20.25}{\gram}
+^D
+[Para [Str "10.0\160g\8211\&20.25\160g"]]
+```
+