doc/Makefile: incremental and parallel rebuild of the synopsis

Enough dependencies have been added so that

* If nothing has changed, MkSynopsis.hs will not be run, so synopisis.html
  will not be needlessly regenerated.
* You can use 'make -j' to build examples for different languages in parallel.

Hopefully 'make synopsis' produces the exact same result as before, but if
it turns out that some dependencies are missing and something is not
rebuilt despite of changes, 'make clean' can be used to force a full rebuild.

doc/Makefile

@@ -1,56 +1,49 @@
-.PHONY: abstract synopsis
+.PHONY: abstract synopsis index status
 
-all: exx synopsis
+all: synopsis
 
 GF_alltenses=$(GF_LIB_PATH)/alltenses
+GF=gf
+GFDOC=gfdoc
 
 index:
 	txt2tags -thtml index.txt
 status:
 	txt2tags -thtml status.txt
-synopsis:
-	runghc MkSynopsis.hs
+
+synopsis: synopsis.html
+
+S=../src
+
+# List of languages extracted from MkSynopsis.hs
+LANGS=Afr Bul Cat Chi Dan Dut Eng Est Eus Fin Fre Ger Gre Hin Ice Ita Jpn Lav Mlt Mon Nep Nor Nno Pes Pnb Pol Ron Rus Snd Spa Swe Tha Urd
+
+# This list was constructed by observing what files MkSynopsis.hs reads
+SRC_FILES=$S/abstract/Common.gf $S/abstract/Cat.gf $S/api/Constructors.gf $S/abstract/Structural.gf $(patsubst %,$S/*/Paradigms%.gf,$(LANGS))
+
+EXAMPLES_OUT=$(patsubst %,api-examples-%.txt,$(LANGS))
+
+synopsis.html: $(EXAMPLES_OUT) $(SRC_FILES)
+	runghc MkSynopsis.hs >out
 
 categories-imagemap.html: categories.dot
 	dot -Tcmapx $^ > $@
 
 abstract:
-	gfdoc -txthtml ../src/abstract/*.gf
-	mv ../src/abstract/*.html abstract
+	$(GFDOC) -txthtml $S/abstract/*.gf
+	mv $S/abstract/*.html abstract
 
-exx-script:
-	runghc MkExx.hs <api-examples.txt >api-examples.gfs
-exx: exx-script
-	gf -retain -s $(GF_alltenses)/TryAfr.gfo <api-examples.gfs >api-examples-Afr.txt
-	gf -retain -s $(GF_alltenses)/TryBul.gfo <api-examples.gfs >api-examples-Bul.txt
-	gf -retain -s $(GF_alltenses)/TryCat.gfo <api-examples.gfs >api-examples-Cat.txt
-	gf -retain -s $(GF_alltenses)/TryChi.gfo <api-examples.gfs >api-examples-Chi.txt
-	gf -retain -s $(GF_alltenses)/TryDan.gfo <api-examples.gfs >api-examples-Dan.txt
-	gf -retain -s $(GF_alltenses)/TryDut.gfo <api-examples.gfs >api-examples-Dut.txt
-	gf -retain -s $(GF_alltenses)/TryEng.gfo <api-examples.gfs >api-examples-Eng.txt
-	gf -retain -s $(GF_alltenses)/TryEst.gfo <api-examples.gfs >api-examples-Est.txt
-	gf -retain -s $(GF_alltenses)/TryEus.gfo <api-examples.gfs >api-examples-Eus.txt
-	gf -retain -s $(GF_alltenses)/TryFin.gfo <api-examples.gfs >api-examples-Fin.txt
-	gf -retain -s $(GF_alltenses)/TryFre.gfo <api-examples.gfs >api-examples-Fre.txt
-	gf -retain -s $(GF_alltenses)/TryGer.gfo <api-examples.gfs >api-examples-Ger.txt
-	gf -retain -s $(GF_alltenses)/TryGre.gfo <api-examples.gfs >api-examples-Gre.txt
-	gf -retain -s $(GF_alltenses)/TryHin.gfo <api-examples.gfs >api-examples-Hin.txt
-	gf -retain -s $(GF_alltenses)/TryIce.gfo <api-examples.gfs >api-examples-Ice.txt
-	gf -retain -s $(GF_alltenses)/TryIta.gfo <api-examples.gfs >api-examples-Ita.txt
-	gf -retain -s $(GF_alltenses)/TryJpn.gfo <api-examples.gfs >api-examples-Jpn.txt
-	gf -retain -s $(GF_alltenses)/TryLav.gfo <api-examples.gfs >api-examples-Lav.txt
-	gf -retain -s $(GF_alltenses)/TryMlt.gfo <api-examples.gfs >api-examples-Mlt.txt
-	gf -retain -s $(GF_alltenses)/TryMon.gfo <api-examples.gfs >api-examples-Mon.txt
-	gf -retain -s $(GF_alltenses)/TryNep.gfo <api-examples.gfs >api-examples-Nep.txt
-	gf -retain -s $(GF_alltenses)/TryNor.gfo <api-examples.gfs >api-examples-Nor.txt
-	gf -retain -s $(GF_alltenses)/TryNno.gfo <api-examples.gfs >api-examples-Nno.txt
-	gf -retain -s $(GF_alltenses)/TryPes.gfo <api-examples.gfs >api-examples-Pes.txt
-	gf -retain -s $(GF_alltenses)/TryPnb.gfo <api-examples.gfs >api-examples-Pnb.txt
-	gf -retain -s $(GF_alltenses)/TryPol.gfo <api-examples.gfs >api-examples-Pol.txt
-	gf -retain -s $(GF_alltenses)/TryRon.gfo <api-examples.gfs >api-examples-Ron.txt
-	gf -retain -s $(GF_alltenses)/TryRus.gfo <api-examples.gfs >api-examples-Rus.txt
-	gf -retain -s $(GF_alltenses)/TrySnd.gfo <api-examples.gfs >api-examples-Snd.txt
-	gf -retain -s $(GF_alltenses)/TrySpa.gfo <api-examples.gfs >api-examples-Spa.txt
-	gf -retain -s $(GF_alltenses)/TrySwe.gfo <api-examples.gfs >api-examples-Swe.txt
-	gf -retain -s $(GF_alltenses)/TryTha.gfo <api-examples.gfs >api-examples-Tha.txt
-	gf -retain -s $(GF_alltenses)/TryUrd.gfo <api-examples.gfs >api-examples-Urd.txt
+
+api-examples.gfs: api-examples.txt
+	runghc MkExx.hs < $< > $@
+
+
+# Since .gfo files aren't self-contained, the dependencies given here are
+# incomplete. But I am thinking that the Try%.gfo file will always be newer
+# than any other files it depends on, so the rule will trigger when
+# needed anyway. //TH 2018-10-22
+api-examples-%.txt: $(GF_alltenses)/Try%.gfo api-examples.gfs
+	GF_LIB_PATH=$(GF_LIB_PATH) $(GF) -retain -s $< <api-examples.gfs >$@
+
+clean:
+	rm -rf out synopsis.txt api-examples.gfs $(EXAMPLES_OUT)

doc/MkExxTable.hs

@@ -1,7 +1,7 @@
 module MkExxTable (getApiExx, ApiExx, prApiEx, mkEx) where
 
-import System.Cmd
-import System.Environment
+--import System.Cmd
+import System.Environment(getArgs)
 import qualified Data.Map as M
 import Data.Char
 

doc/MkSynopsis.hs

@@ -1,6 +1,6 @@
 import MkExxTable
-import System.Cmd
-import System.Environment
+import System.Process(system)
+import System.Environment(getArgs)
 import Data.Char
 import Data.List
 import qualified Data.ByteString.Char8 as BS
@@ -16,7 +16,7 @@ synopsis = "synopsis.txt"
 -- the language in which revealed examples are shown
 revealedLang = "Eng"
 
--- all languages shown
+-- all languages shown (a copy of this list appears in Makefile)
 apiExxFiles = ["api-examples-" ++ lang ++ ".txt" | lang <- words
 --   "Eng Chi"
   "Afr Bul Cat Chi Dan Dut Eng Est Eus Fin Fre Ger Gre Hin Ice Ita Jpn Lav Mlt Mon Nep Nor Nno Pes Pnb Pol Ron Rus Snd Spa Swe Tha Urd"