Crystal: Can you pass Operators to Macro's?

[sancarn]

E.G.

macro test(a,b,operator)
  {{a}}{{operator}}{{b}}
end
test 1, 2, +

Testing this code will throw a syntax error Syntax error in eval:4: unexpected token: EOF

Alternatively when sending a symbol:

macro test(a,b,operator)
  {{a}}{{operator}}{{b}}
end
test 1, 2, :+

Crystal throws a Error in line 4: macro didn't expand to a valid program, it expanded to... error because it expanded to 1:+2, which isn't correct for obvious reasons.

Can we convert an ASTNode into a literal or something along those lines?

[bcardiff]

Macros arguments needs to be valid AST nodes. Sometimes you will be able to change the meaning of the node during the expansion of the macros. But for binary operators that is not possible since + is not valid expression as a whole.

FYI: this is better in stackoverflow

[straight-shoota]

Using a symbol is a good solution, but you need to expand it not as a symbol but as an operator using {{ operator.id }}.

macro test(a,b,operator)
  {{a}}{{operator.id}}{{b}}
end
test 1, 2, :+