Add support for calling Functions in Strings [Puppet 4]

[PierreR]

notify { 'need_coffee':
  message => "I need a cup of coffee. Remind me in ${fqdn_rand(10)} minutes.",
}

[bartavelle]

This is a large feature, and I will certainly not have time to implement it in the foreseeable future ...

[bartavelle]

This is tricky because there are two use cases:

• ${foo}, where it should be interpreted as variable $foo
• ${foo[$bar]}, where it should be interpreted as $foo[$bar]
• ${foo($bar)}, where it should be interpreted as foo($bar)

Perhaps the simplest solution would be to add the full expression parser after try simpleIndexing and try rvariable on lines 204-207 of the parser.

[bartavelle]

This is really horrible:

"${::interfaces.split(',')[3]}"

[bartavelle]

This does't handle the case where you do arbitrary stuff to a variable, but should parse most expressions. To be toroughly tested!

[PierreR]

The commit broke this kind of code:

class test {
  exec {
    "test":
      command     => "test",
      onlyif      => "grep '^${sanitised_title}$'",
  }
}

puppetresources --parse test.pp
puppetresources: parse error:ParseError {errorPos = SourcePos {sourceName = "test.pp", sourceLine = Pos 5, sourceColumn = Pos 49} :| [], errorUnexpected = fromList [Tokens ('\'' :| "")], errorExpected = fromList [Tokens (':' :| ":"),Tokens ('{' :| "")], errorCustom = fromList []}
CallStack (from HasCallStack):
  error, called at progs/PuppetResources.hs:374:24 in main:Main

[bartavelle]

Just pushed a change that should fix that.

[PierreR]

Doesn't break anymore in any obvious way. Thanks.