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”?

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When I read the book "A Practical approach to compiler construction" the chapter4 "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?



(Since my reputation is less than 10, so I just copy the image url. I will change later after the reputation is full.)



https://i.stack.imgur.com/Bd8Zm.png




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    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 at 20:50














up vote
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When I read the book "A Practical approach to compiler construction" the chapter4 "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?



(Since my reputation is less than 10, so I just copy the image url. I will change later after the reputation is full.)



https://i.stack.imgur.com/Bd8Zm.png




automata




share|cite|improve this question











migrated from math.stackexchange.com Jul 23 at 19:17


This question came from our site for people studying math at any level and professionals in related fields.










  • 1




    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 at 20:50












up vote
0
down vote

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up vote
0
down vote

favorite











When I read the book "A Practical approach to compiler construction" the chapter4 "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?



(Since my reputation is less than 10, so I just copy the image url. I will change later after the reputation is full.)



https://i.stack.imgur.com/Bd8Zm.png




automata




share|cite|improve this question











When I read the book "A Practical approach to compiler construction" the chapter4 "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?



(Since my reputation is less than 10, so I just copy the image url. I will change later after the reputation is full.)



https://i.stack.imgur.com/Bd8Zm.png





automata





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asked Jul 23 at 14:11









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migrated from math.stackexchange.com Jul 23 at 19:17


This question came from our site for people studying math at any level and professionals in related fields.






migrated from math.stackexchange.com Jul 23 at 19:17


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  • 1




    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 at 20:50












  • 1




    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 at 20:50







1




1




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 at 20:50




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 at 20:50










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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).






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    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).






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      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).






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        up vote
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        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).






        share|cite|improve this answer













        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).







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        answered Jul 23 at 20:51









        D.W.♦

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