Are Ruby formatted strings and interpolated strings identical in behaviour? -

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do following 2 lines of code behave in same way despite different implementations

values.map{ |k,v| __send__('%s=' % k.to_s, v) } values.map{ |k,v| __send__("#{k.to_s}=", v) }

the second line more common ruby idiom wondering why other method used when in rails core expect use idiomatic ruby.

they not absolutely identical. instance, first example call string#%, if method redefined strange reason, might different result. standard definition of string#%, strings computed same, both expressions have same result.

btw, there's no need to_s in example, , assuming send has not been redefined (and equivalent __send__):

values.map{ |k,v| send("#{k}=", v) }

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