The title would probably be confusing, but I could not make it better than this. I noticed that most programming languages are limited to the alphanumerical set along with the special characters present in a general keyboard. I wondered if this posed a barrier for developers on what characters they were limited to program in, or if it was intentional from the start that these keys would be the most optimal characters for a program to be coded in by a human and was later adopted as a standard for every user. Basically, are the modern keyboards built around programming languages or are programming languages built around these keyboards?
Programming languages are build around the standard keyboard. Keyboards had most of the symbols you’re thinking of from their typewriter days. You can see most of the special characters in these small typewriters from the mid 1900s.
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With things like electric Wheel Writer typewriters, adding extra keys and symbols were less of a complexity issue and you started to see a few more extra symbols.
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Recognize that there never has been a hard standard for layouts and symbols, just the industry copying and converging on systems that became popular.