examples of syntax for RubyDo

rubydo.cr

# goal: pass code to a Ruby interpreter running in background as a daemon

greeting = "hello"
source   = "Ruby"

# desired syntax, which is impossible because the Crystal parser & lexer cannot ignore everything between `ruby do` & `end`
ruby do |greeting, source|
  # put Ruby code here as just part of a normal block:
  puts "#{greeting} from #{source}!"
end

# less pretty, but possible:
ruby(greeting, source, <<-RUBY
  puts "#{greeting} from #{source}!"
RUBY)
# this would require the code-string being last after an arbitrary number of other arguments...

# maybe something like this would work...?
ruby do |greeting, source|
  <<-RUBY
    puts "#{greeting} from #{source}!"
  RUBY
end
# can you pass a string as the block?  I suppose so...

# the best option may be something like this:
ruby "./greet.rb", [greeting, source]
# just pass an array of variables to the ruby file
# the problem is that you lose the names of the variables: they're just ordered arguments...
# perhaps Crystal can iterate through the array, and create a string like this to eval with the Ruby file:
#     greeting = "hello"
#     source = "Ruby"

# then it might be possible to do things like this:
salutation = ruby "./greet.rb", {time: build}, [greeting, source]
salutation = ruby "./greet.rb", {time: run},   [greeting, source]  # run time being the default
# build time might use a macro to replace the ruby call with the results... not sure if that's possible/sensible though