Code review of grep coded in rust

You write standard JavaScript, Ruby or Python scripts.
However, lines starting with a dot (.) go straight to the output.
To expand JavaScript/Ruby/Python expressions within dotted lines use @{expr} construct.

Hardware vendors like to add Unique Selling Points to their devices to convince you to buy them instead of someone else's. Of course, this typically leads to hardware vendors desperately copying each other's Unique Selling Points in a process eerily reminiscent of evolution's Red Queen Effect, all desperately trying to run faster than each other in order to stay in the same place. Putting effort into standardisation would risk them falling behind vendors who choose not to, so in the absence of some external force to compel them, vendor-specific solutions proliferate.

Dictionary based word corrector coded in different language with explanation.