How to remove left recursion from A -> Aα | ε

Question

I think the left-recursion for this grammar is not removable. Correct me if I am wrong. α is Alpha that is a Non-terminal ε is Epsilon.

Not sure if this is off-topic for this site or not, but you can just swap `A -> αA | ε`. Both rule definitions will be equivalent to the regular expresion `α*`, that is, a sequence of as many alpha characters you wish (including none). — Mephy, Jun 09 '20 at 16:08

score 1 · Accepted Answer · answered Jun 09 '20 at 22:24

Left recursion can be removed from the grammar; Here is the grammar without left recursion:

A -> A' | ε
A' -> α A

You could also do how @Mephy did with right recursion:

A -> α A | ε

Note that (as @Mephy said) this grammar is just zero or more αs (α*).

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