Instancing

Raptor files can be instanced, which makes them work as a template.

Instanced files can be recognized by ending in @.rapt (for FROM) or @.rinc (for INCLUDE).

File names and syntax

The table above shows some examples of instanced and non-instanced Raptor files.

Beware

It is invalid to reference an instanced file without an instance.

For example, FROM server@ or FROM base@value would both fail to compile.

Therefore, when writing a new Raptor file, you need to determine if it needs to be instanced, and name the file accordingly.

So far, we have seen how to create templated (instanced) Raptor files, and how to reference them to provide a value.

Now we will see how to use the provided value, so that instancing becomes useful. Let us start the simplest possible example

build-stamp@.rinc

WRITE "We are instance {{instance}}\n" /root/build-stamp.txt

This writes a human-readable line of text to a file, including the instance id.

Now we can use it from another file:

server.rapt

# Will write "We are instance 1\n" to /root/build-stamp.txt
INCLUDE build-stamp@1