Timeline for How to generate regular expression for language of regular expressions?
Current License: CC BY-SA 3.0
15 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jan 14, 2018 at 19:02 | comment | added | reinierpost | Just for the record: using regular expressions with limited nesting depth isn't good enough: they cannot describe all regular languages, as shown in 1963. | |
| Jul 14, 2017 at 16:40 | vote | accept | Desperado | ||
| Jul 14, 2017 at 16:15 | answer | added | Yuval Filmus | timeline score: 2 | |
| Jul 14, 2017 at 16:14 | comment | added | Desperado | I want to create a regular expression that accepts a language of regular expressions and this language of regular expressions should not contain nested brackets. Its the demand of question you can say. | |
| Jul 14, 2017 at 16:11 | history | edited | Raphael |
edited tags
|
|
| Jul 14, 2017 at 16:10 | comment | added | Raphael | I have the strong feeling that "regular expressions without nested brackets" are not regular expressions at all, but a properly weaker formalism. | |
| Jul 14, 2017 at 14:33 | review | Close votes | |||
| Jul 30, 2017 at 3:03 | |||||
| Jul 14, 2017 at 14:09 | history | edited | Desperado | CC BY-SA 3.0 |
deleted 12 characters in body
|
| Jul 14, 2017 at 14:05 | comment | added | reinierpost | OK, in that case change your third sentence to: what would be a regular expression that describes the language of such regular expressions? By the way, I suggest you try finding an expression for r.e.s with one pair of brackets first, then two pairs of brackets, then use a Kleene star to handle an arbitrary number of pairs of brackets. | |
| Jul 14, 2017 at 11:39 | comment | added | Desperado | This is not about POSTFIX notations. I have to create a Regular Expression, that accepts regular expressions of any form but without nested brackets. $[0+1]^{\star} \cup [01]^{\star}$ is accepted as this does not have nested brackets but $[0+[01]^{\star}]^{\star}$ is not accepted because it has nested brackets. | |
| Jul 14, 2017 at 11:20 | comment | added | Hendrik Jan | Did you consider postfix expressions? They are bracket-free. Rather than $S+T$ write $ST+$, etcetera. | |
| Jul 14, 2017 at 7:50 | comment | added | Desperado | A Regular Expression cannot handle nested brackets. Here I have to come up with a regular expression that accepts a language of regular expressions. So you see $[0+1]^{\star}$ is a regular expression that should be generated by the Regular Expression. | |
| Jul 14, 2017 at 7:16 | comment | added | reinierpost | If you don't want to generate nested brackets, how will you ever describe all regular expressions? | |
| Jul 14, 2017 at 4:33 | history | edited | Desperado | CC BY-SA 3.0 |
added 2 characters in body
|
| Jul 14, 2017 at 1:42 | history | asked | Desperado | CC BY-SA 3.0 |