Variable Checker [GAME]

Question

Hey Developer's.... let's play a game..

Enter a variable name with spaces and special characters. The output should be represented by the following rules...

RULES..

1. variable names starting with a digit should show an error message.
2. spaces between variable name should be deleted and next word should start with uppercase. more than 1 space can be der
eg. input=my input output=myInput
3. each special character should be replaced by '_' sign.

So, let's give it a try...every language welcomed..

Answer 1

https://code.sololearn.com/cf630LgoZfLB/?ref=app

Answer 2

Ruby:
https://code.sololearn.com/cUR8y9X9fngg/#rb

Answer 3

My go in Python: https://code.sololearn.com/cww0JcppOD07/#py

Answer 4

https://code.sololearn.com/cpvzfnHgh5Q6/?ref=app

Answer 5

https://code.sololearn.com/cpiUcFI1vQuN/?ref=app