[R] A question on regular expression

[Christofer Bogaso]

Thanks Bert,

This works, but if in my text there are more than one patterns then
fails to generate desired result.

library(stringr)
str_extract_all(paste("ab{cd$ }ed", "ab{cad$ }ed", collapse = " "),
".*(\\{.*\\}).*")

This generates below -

[[1]]

[1] "ab{cd$ }ed ab{cad$ }ed"

I was expecting I would get a vector of length 2 with desired pattern.

Where did I make any mistake?

Thanks,

On Thu, Sep 12, 2019 at 10:29 PM Bert Gunter <bgunter.4567 using gmail.com> wrote:
>
> > sub(".*(\\{.*\\}).*", "\\1","ab{cd$ }ed")
> [1] "{cd$ }"
>
> Use ".+" instead of ".*" within the {} if you don't want to return empty {}'s.
>
> You might wish to use the stringr package for string matching and manipulation, as it provides a more user friendly and consistent interface to these tasks.
>
>
> Bert Gunter
>
> "The trouble with having an open mind is that people keep coming along and sticking things into it."
> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
>
>
> On Thu, Sep 12, 2019 at 9:31 AM Christofer Bogaso <bogaso.christofer using gmail.com> wrote:
>>
>> Hi,
>>
>> I am wondering on what is the correct way to select a pattern which goes as -
>>
>> {"(any character with any length)"}
>>
>> The expressions " {" " and " "} " both are included in the pattern.
>>
>> For example, the lookup of the above pattern in the text "
>> {"asaf455%"}57573blabla " will result in {"asaf455%"}
>>
>> Any help will be highly appreciated.
>>
>> Thanks,
>>
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