rubygems - Can't install a ruby gem because of an error? -

Hey, trying to install a ruby ​​gem but I get the following error:

  error: failed to create Mani native extension / system / libraries / framworks / ruby ​​framework / version / 1.8 / usr / bin / ruby ​​extconf.rb mkmf.rb / router / system / library / framework / rb Framework / Version / 1/8 / UR / LIB / RUB / RBI H  

I'm not sure what's going on here. Is there anyone who knows what is going on and how to fix it?

Thank you!

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