I think it depends. Is learning a new programming language a waste of time compare to getting better with the current programming language that you knew already?
While I'm learning Ruby, it did not make me a better Java programmer. I still suck at Java programming.
Reading books like Code Complete, Pragmatic Programmer, Clean Code, and reading Zen of Python (import this) help me to become a better programmer; but learning Python does not help me to become a better developer. Reading better code (other people's or projects's) do make me know more.
I finally understand what does it mean with the phrase "no matter what they tell you, it's always a people problem.". Languages have nothing to do with it.
Ruby introduced me to the ideas of first class functions, closures, and higher order functions and the design patterns that can be easily implemented using them. These same patterns can be implemented in Java, albeit with a much more verbose syntax. Most Java programmers are unaware of even these basic functional concepts and it shows because they end up copy-pasting a lot of code they don't have to and writing silly functions that can be easily implemented in terms of functions like map, filter, and reduce.
Yes, learning a new language can and does make you a better programmer if it introduces new concepts you can apply to other languages.
While I'm learning Ruby, it did not make me a better Java programmer. I still suck at Java programming.
Reading books like Code Complete, Pragmatic Programmer, Clean Code, and reading Zen of Python (import this) help me to become a better programmer; but learning Python does not help me to become a better developer. Reading better code (other people's or projects's) do make me know more.
I finally understand what does it mean with the phrase "no matter what they tell you, it's always a people problem.". Languages have nothing to do with it.