Ruby - pass variable to eval method

Question

I have a variable which reference a method, I call the method with the eval keyword

a_test = "myvariable"
eval a_test


def myvariable
(...)
end

I would like to pass a variable to method, such as

def myvariable(var1)
(...)
end

Is anyone familiar with any "idiom" way of accomplishing this. Doing something like

eval a_test "string_test"

will naturally fail since a lookup will be done by the interpreter for a function called "a_test"

Just to make it clean: myvariable in this case is not a variable. — Guilherme Bernal
– Guilherme Bernal, Commented Nov 24, 2011 at 20:55

Rimian · Accepted Answer · 2012-11-29 11:18:57Z

14

This should work for you

def myvariable(foo)
  return "hello #{foo}"
end
a_test = "myvariable"

eval "puts #{a_test}('world')"

#=> hello world

In ruby though, it would be more appropriate to do something like this

def myvariable(foo)
  return "hello #{foo}"
end
a_test = "myvariable"

puts send(a_test, 'world')

#=> hello world

Read more about send

Rimian

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answered Nov 24, 2011 at 19:36

maček

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