How to produce a .js file from a haskell source file with haste? -

so noticed, while answering this question, 1 asked question appears javascript developer. , code wrote in haskell easy enough, thought give haste try , try compile javascript.

so, downloaded windows binary package of haste (why .msi require reboot?!!?), added path, issued haste-cabal update , haste-cabal install split , after bit of reading output of hastec --help, issued:

ps e:\h\stackoverflow> hastec -o hexagon.js --pretty-print hexagon.hs
best guess on how output looking for.

opposite expectation, haste output this:

hastec.exe: user error (shell expression failed in readmodule: data.binary.get.runget @ position 8: not enough bytes)

so, question: have java script source file?

is possible have old version of haste lying around, or have intermediate files (.jsmod, instance) different version of compiler in source directory? sounds (quite unhelpful) error message haste produces when runs corrupted intermediate file.

check version of binary you're calling expect (hastec --version). then, try getting rid of intermediate files in directory files in %userprofile%\appdata\roaming\haste, reinstalling split, , recompiling -fforce-recomp flag. should add main function, haste has entry point program start linking. if want make haskell function available external javascript, can use export foreign function interface:

{-# language overloadedstrings #-} module main import haste.foreign import hexagon  main = export "picture" hexagon.picture 

you want compile program --onexec flag, make sure main runs , exports picture when loaded, , not on page load default:

> hastec -o hexagon.js --pretty-print --onexec hexagon.hs 

after doing this, code included after hexagon.js able call e.g. haste.picture(5); in order produce picture of size 5.

(re: msi installer requiring reboot, required since adds haste binaries %path%, not take effect immediately. assume re-login enough make take effect, however.)