Make Ceylon scriptable

[CeylonMigrationBot]

[@FroMage] Needs some thinking

[Migrated from ceylon/ceylon-spec#200]

[lucaswerkmeister]

I’m not sure what you mean by point 10. ceylonb isn’t mine, it was added by @quintesse (#6080). And I don’t think it makes sense to have /bin/ceylonb – if you’ve installed a Ceylon package (which the /bin path implies), then you don’t need the bootstrap version, you might as well use ceylon directly.

[HenningB]

Sorry, I mean ceylond. Now corrected in my previous comment.

ceylond because it won't be a big issue if the scripts get recompiled each time (if we don't get the caching right). Or if the user wants to use Ceylon script for building software, like Gradle which also starts a deamon.

[luolong]

Will ceylond be installed as part of official ceylon distribution or do I have to install it separately?

[jvasileff]

Various hash-bang lines are suggested above, such as:

• #!/bin/ceylon run
• #!/bin/ceylon run --compile
• #!/usr/bin/ceylon script

But there are a couple problems.

First, the Ceylon installation directory is not likely to be consistent across machines (it may be /usr/local/bin/ceylon, ~/opt/ceylon/bin, /usr/bin/ceylon, etc., etc.) For portable scripts, this would be solved by using env to search the user's path for ceylon, as in:

#!/usr/bin/env ceylon run --compile

But the second problem is that on linux, only a single argument can be provided to hash-bang commands. The above would be interpreted as #!/usr/bin/env "ceylon run --compile", which wouldn't work. Nor would #!/bin/ceylon run --compile.

So I think we probably need a ceylon-script command that requires no arguments. The suggested usage would be:

#!/usr/bin/env ceylon-script

Note that the caller of the script may also provide arguments to the script.