why it said the "The left recursion has been removed at the cost of an extra non-terminal symbol(E1) and a little extra complexity"?

Question

When I read the book "A Practical approach to compiler construction" the chapter 4 "approaches to syntax analysis" and the section 4.2.3.3 Left Recursion, it says:

"The left recursion has been removed at the cost of an extra non-terminal symbol"

I have no idea why say that, since $A_1$ still contain recursion?

Is there any chance you could use an image that is cropped to contain just the relevant part of the quote, rather than an image of the entire page? Also can you provide a full reference for the book (both title & authors)? — D.W., Jul 23 '18 at 20:50

score 1 · Answer 1 · answered Jul 23 '18 at 20:51

1

That grammar has recursion but not left recursion. Check the definition of left recursion (e.g., https://en.wikipedia.org/wiki/Left_recursion, or consult your favorite textbook on formal languages).

answered Jul 23 '18 at 20:51

D.W.

159,275
20
227
470

why it said the "The left recursion has been removed at the cost of an extra non-terminal symbol(E1) and a little extra complexity"?

1 Answers1