给定 final String[] NECESSARY_PERMISSIONS = new String[] {Manifest.permission.GET_ACCOUNTS };
if (ContextCompat.checkSelfPermission(DialerHomeActivity.this,
Manifest.permission.GET_ACCOUNTS) == PackageManager.PERMISSION_GRANTED) {
//Permission is granted
} else {
//ask for permission
ActivityCompat.requestPermissions(
DialerHomeActivity.this,
NECESSARY_PERMISSIONS, 123);
}
MyModule.hs我可以使用$ cat MyModule.hs
{-# OPTIONS_GHC -main-is MyModule.main #-}
module MyModule where
main = print "MyModule.Main"
选项
app
-main-is但是当我省略$ ghc -o app -main-is MyModule.main MyModule.hs
[1 of 1] Compiling MyModule ( MyModule.hs, MyModule.o ) [flags changed]
Linking app ...
选项并希望ghc将使用-main-is pragma时，它不起作用。
OPTIONS_GHC document提及$ ghc -o app MyModule.hs
[1 of 1] Compiling MyModule ( MyModule.hs, MyModule.o )
<no location info>: error:
output was redirected with -o, but no output will be generated
because there is no Main module.
作为-main-is选项类型，这意味着应该可以通过编译语(ref)使用
问题：
dynamic pragma？-main-is吗？