The following may be of use (it gives the parse tree of the text):> z <- as.list(parse(text = "function(x)x %*% x")) > z[[1]]function(x) x %*% x> z[[c(1,1)]]`function`> z[[c(1,2)]]$x> z[[c(1,3)]]x %*% x> z[[c(1,3,1)]]`%*%`> z[[c(1,3,2)]]x> z[[c(1,3,3)]]x Bert Gunter On Fri, Sep 6, 2019 at 10:14 AM Wang Jiefei <szwjf08 at gmail.com> wrote:> If you are looking for an R code parser, I think the `parse` and `eval` > function might be a good start point. See the example below. > > > parse(text="function(x)message(x)") > expression(function(x)message(x)) > > eval(parse(text="function(x)message(x)")) > function(x)message(x) > > Best, > Jiefei > > On Fri, Sep 6, 2019 at 12:55 PM Golden, Shelby <GoldenS at njhealth.org> > wrote: > >> Hello Bert, >> >> Thank you for the reply and your clarifications. Yes, it might be helpful >> to look into R?s formal grammar to see how ?function? parses input to >> delegate correct syntax. Is that accessible online? >> >> Thank you, >> Shelby >> >> >> From: Bert Gunter <bgunter.4567 at gmail.com> >> Date: Friday, September 6, 2019 at 10:44 AM >> To: "Golden, Shelby" <GoldenS at NJHealth.org> >> Cc: "r-help at R-project.org" <r-help at r-project.org>, "Gillenwater, Lucas" < >> GILLENWATERL at NJHEALTH.ORG> >> Subject: Re: [R] [R-devel] Source Code for function >> >> 1. This is a plain text list; all html is stripped. So there is no red >> highlighting. >> >> 2. There is no "source code" for "function" -- it is a reserved keyword. >> Or are you looking for R's formal grammar -- e.g. how it parses input to >> determine correct syntax? >> >> >> >> 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 Fri, Sep 6, 2019 at 8:51 AM Golden, Shelby <GoldenS at njhealth.org >> <mailto:GoldenS at njhealth.org>> wrote: >> Hi all, >> >> I have been attempting to access the source code for the keyword >> ?function? to better understand how it assigns and stores logical inputs, >> like in the subset() [base] function. Does anyone know how I can access the >> source code for this? >> >> For example, if I have >> norm <- function(x){ >> sqrt(x%*%x)) >> } >> I am looking for the source code for the ?function? portion, highlighted >> in red. >> >> Thank you for your time and assistance, >> Shelby Golden >> Lab Researcher Technician >> Dr. Russell Bowler?s Lab >> Department of Medicine >> National Jewish Health in Denver, CO >> Phone: (303) 270-2598 >> >> NOTICE: This email message is for the sole use of the intended >> recipient(s) and may contain confidential and privileged information. Any >> unauthorized review, use, disclosure or distribution is prohibited. If you >> are not the intended recipient, please contact the sender by reply email >> and destroy all copies of the original message. >> [[alternative HTML version deleted]] >> >> ______________________________________________ >> R-help at r-project.org<mailto:R-help at r-project.org> mailing list -- To >> UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help< >> http://mx2.njhealth.org:32224/?dmVyPTEuMDAxJiZmMWRiYmMxZjFmNmI5ZDBkMz01RDcyOEQwN18yMjk2OF8zOTk2XzEmJjljNzlmMDA4YWRmZTZjMz0xMjMzJiZ1cmw9aHR0cHMlM0ElMkYlMkZzdGF0JTJFZXRoeiUyRWNoJTJGbWFpbG1hbiUyRmxpc3RpbmZvJTJGci1oZWxw >> > >> PLEASE do read the posting guide >> http://www.R-project.org/posting-guide.html< >> http://mx2.njhealth.org:32224/?dmVyPTEuMDAxJiZlMTkwYmMwMzFlNjk4ZTAzNz01RDcyOEQwN18yMjk2OF8zOTk2XzEmJmFkYTkxMWRkMWRhZTFkNz0xMjMzJiZ1cmw9aHR0cCUzQSUyRiUyRnd3dyUyRVItcHJvamVjdCUyRW9yZyUyRnBvc3RpbmctZ3VpZGUlMkVodG1s >> > >> and provide commented, minimal, self-contained, reproducible code. >> >> [[alternative HTML version deleted]] >> >> ______________________________________________ >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide >> http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. >> >[[alternative HTML version deleted]]
You might also want to look at the codetools package, for example the showTree function " Prints a Lisp-style representation of R expression."> library(codetools)> showTree(quote(x %*% x))(%*% x x)> showTree(quote(a+b))(+ a b)> showTree(quote(y ~ a+b))(~ y (+ a b)) On Fri, Sep 6, 2019 at 2:30 PM Bert Gunter <bgunter.4567 at gmail.com> wrote:> > The following may be of use (it gives the parse tree of the text): > > > z <- as.list(parse(text = "function(x)x %*% x")) > > z[[1]] > function(x) x %*% x > > z[[c(1,1)]] > `function` > > z[[c(1,2)]] > $x > > z[[c(1,3)]] > x %*% x > > z[[c(1,3,1)]] > `%*%` > > z[[c(1,3,2)]] > x > > z[[c(1,3,3)]] > x > > > Bert Gunter > > > > On Fri, Sep 6, 2019 at 10:14 AM Wang Jiefei <szwjf08 at gmail.com> wrote: > > > If you are looking for an R code parser, I think the `parse` and `eval` > > function might be a good start point. See the example below. > > > > > parse(text="function(x)message(x)") > > expression(function(x)message(x)) > > > eval(parse(text="function(x)message(x)")) > > function(x)message(x) > > > > Best, > > Jiefei > > > > On Fri, Sep 6, 2019 at 12:55 PM Golden, Shelby <GoldenS at njhealth.org> > > wrote: > > > >> Hello Bert, > >> > >> Thank you for the reply and your clarifications. Yes, it might be helpful > >> to look into R?s formal grammar to see how ?function? parses input to > >> delegate correct syntax. Is that accessible online? > >> > >> Thank you, > >> Shelby > >> > >> > >> From: Bert Gunter <bgunter.4567 at gmail.com> > >> Date: Friday, September 6, 2019 at 10:44 AM > >> To: "Golden, Shelby" <GoldenS at NJHealth.org> > >> Cc: "r-help at R-project.org" <r-help at r-project.org>, "Gillenwater, Lucas" < > >> GILLENWATERL at NJHEALTH.ORG> > >> Subject: Re: [R] [R-devel] Source Code for function > >> > >> 1. This is a plain text list; all html is stripped. So there is no red > >> highlighting. > >> > >> 2. There is no "source code" for "function" -- it is a reserved keyword. > >> Or are you looking for R's formal grammar -- e.g. how it parses input to > >> determine correct syntax? > >> > >> > >> > >> 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 Fri, Sep 6, 2019 at 8:51 AM Golden, Shelby <GoldenS at njhealth.org > >> <mailto:GoldenS at njhealth.org>> wrote: > >> Hi all, > >> > >> I have been attempting to access the source code for the keyword > >> ?function? to better understand how it assigns and stores logical inputs, > >> like in the subset() [base] function. Does anyone know how I can access the > >> source code for this? > >> > >> For example, if I have > >> norm <- function(x){ > >> sqrt(x%*%x)) > >> } > >> I am looking for the source code for the ?function? portion, highlighted > >> in red. > >> > >> Thank you for your time and assistance, > >> Shelby Golden > >> Lab Researcher Technician > >> Dr. Russell Bowler?s Lab > >> Department of Medicine > >> National Jewish Health in Denver, CO > >> Phone: (303) 270-2598 > >> > >> NOTICE: This email message is for the sole use of the intended > >> recipient(s) and may contain confidential and privileged information. Any > >> unauthorized review, use, disclosure or distribution is prohibited. If you > >> are not the intended recipient, please contact the sender by reply email > >> and destroy all copies of the original message. > >> [[alternative HTML version deleted]] > >> > >> ______________________________________________ > >> R-help at r-project.org<mailto:R-help at r-project.org> mailing list -- To > >> UNSUBSCRIBE and more, see > >> https://stat.ethz.ch/mailman/listinfo/r-help< > >> http://mx2.njhealth.org:32224/?dmVyPTEuMDAxJiZmMWRiYmMxZjFmNmI5ZDBkMz01RDcyOEQwN18yMjk2OF8zOTk2XzEmJjljNzlmMDA4YWRmZTZjMz0xMjMzJiZ1cmw9aHR0cHMlM0ElMkYlMkZzdGF0JTJFZXRoeiUyRWNoJTJGbWFpbG1hbiUyRmxpc3RpbmZvJTJGci1oZWxw > >> > > >> PLEASE do read the posting guide > >> http://www.R-project.org/posting-guide.html< > >> http://mx2.njhealth.org:32224/?dmVyPTEuMDAxJiZlMTkwYmMwMzFlNjk4ZTAzNz01RDcyOEQwN18yMjk2OF8zOTk2XzEmJmFkYTkxMWRkMWRhZTFkNz0xMjMzJiZ1cmw9aHR0cCUzQSUyRiUyRnd3dyUyRVItcHJvamVjdCUyRW9yZyUyRnBvc3RpbmctZ3VpZGUlMkVodG1s > >> > > >> and provide commented, minimal, self-contained, reproducible code. > >> > >> [[alternative HTML version deleted]] > >> > >> ______________________________________________ > >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > >> https://stat.ethz.ch/mailman/listinfo/r-help > >> PLEASE do read the posting guide > >> http://www.R-project.org/posting-guide.html > >> and provide commented, minimal, self-contained, reproducible code. > >> > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.
Thank you all for your reply. I should clarify, that I am looking to understand
why the keyword function can take a logical argument (eg: x<4) and use that
later inside the function's definition for logical evaluations.
Consider this example, which is a simplification of
getAnywhere(subset.data.frame):
x = data.frame("Col1" = c(1, 2, 3, 4, 5), "Col2" = c(6, 7,
8, 9, 10))
test <- function(x, logic){
e <- substitute(logic)
r <- eval(e, x, parent.frame())
r[r]
}
Shelby
?On 9/6/19, 1:02 PM, "R-help on behalf of Richard M. Heiberger"
<r-help-bounces at r-project.org on behalf of rmh at temple.edu> wrote:
You might also want to look at the codetools package, for example the
showTree function " Prints a Lisp-style representation of R
expression."
> library(codetools)
> showTree(quote(x %*% x))
(%*% x x)
> showTree(quote(a+b))
(+ a b)
> showTree(quote(y ~ a+b))
(~ y (+ a b))
On Fri, Sep 6, 2019 at 2:30 PM Bert Gunter <bgunter.4567 at gmail.com>
wrote:
>
> The following may be of use (it gives the parse tree of the text):
>
> > z <- as.list(parse(text = "function(x)x %*% x"))
> > z[[1]]
> function(x) x %*% x
> > z[[c(1,1)]]
> `function`
> > z[[c(1,2)]]
> $x
> > z[[c(1,3)]]
> x %*% x
> > z[[c(1,3,1)]]
> `%*%`
> > z[[c(1,3,2)]]
> x
> > z[[c(1,3,3)]]
> x
>
>
> Bert Gunter
>
>
>
> On Fri, Sep 6, 2019 at 10:14 AM Wang Jiefei <szwjf08 at
gmail.com> wrote:
>
> > If you are looking for an R code parser, I think the `parse` and
`eval`
> > function might be a good start point. See the example below.
> >
> > > parse(text="function(x)message(x)")
> > expression(function(x)message(x))
> > > eval(parse(text="function(x)message(x)"))
> > function(x)message(x)
> >
> > Best,
> > Jiefei
> >
> > On Fri, Sep 6, 2019 at 12:55 PM Golden, Shelby <GoldenS at
njhealth.org>
> > wrote:
> >
> >> Hello Bert,
> >>
> >> Thank you for the reply and your clarifications. Yes, it might
be helpful
> >> to look into R?s formal grammar to see how ?function? parses
input to
> >> delegate correct syntax. Is that accessible online?
> >>
> >> Thank you,
> >> Shelby
> >>
> >>
> >> From: Bert Gunter <bgunter.4567 at gmail.com>
> >> Date: Friday, September 6, 2019 at 10:44 AM
> >> To: "Golden, Shelby" <GoldenS at NJHealth.org>
> >> Cc: "r-help at R-project.org" <r-help at
r-project.org>, "Gillenwater, Lucas" <
> >> GILLENWATERL at NJHEALTH.ORG>
> >> Subject: Re: [R] [R-devel] Source Code for function
> >>
> >> 1. This is a plain text list; all html is stripped. So there
is no red
> >> highlighting.
> >>
> >> 2. There is no "source code" for
"function" -- it is a reserved keyword.
> >> Or are you looking for R's formal grammar -- e.g. how it
parses input to
> >> determine correct syntax?
> >>
> >>
> >>
> >> 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 Fri, Sep 6, 2019 at 8:51 AM Golden, Shelby <GoldenS at
njhealth.org
> >> <mailto:GoldenS at njhealth.org>> wrote:
> >> Hi all,
> >>
> >> I have been attempting to access the source code for the
keyword
> >> ?function? to better understand how it assigns and stores
logical inputs,
> >> like in the subset() [base] function. Does anyone know how I
can access the
> >> source code for this?
> >>
> >> For example, if I have
> >> norm <- function(x){
> >> sqrt(x%*%x))
> >> }
> >> I am looking for the source code for the ?function? portion,
highlighted
> >> in red.
> >>
> >> Thank you for your time and assistance,
> >> Shelby Golden
> >> Lab Researcher Technician
> >> Dr. Russell Bowler?s Lab
> >> Department of Medicine
> >> National Jewish Health in Denver, CO
> >> Phone: (303) 270-2598
> >>
> >> NOTICE: This email message is for the sole use of the intended
> >> recipient(s) and may contain confidential and privileged
information. Any
> >> unauthorized review, use, disclosure or distribution is
prohibited. If you
> >> are not the intended recipient, please contact the sender by
reply email
> >> and destroy all copies of the original message.
> >> [[alternative HTML version deleted]]
> >>
> >> ______________________________________________
> >> R-help at r-project.org<mailto:R-help at r-project.org>
mailing list -- To
> >> UNSUBSCRIBE and more, see
> >> https://stat.ethz.ch/mailman/listinfo/r-help<
> >>
http://mx2.njhealth.org:32224/?dmVyPTEuMDAxJiZmMWRiYmMxZjFmNmI5ZDBkMz01RDcyOEQwN18yMjk2OF8zOTk2XzEmJjljNzlmMDA4YWRmZTZjMz0xMjMzJiZ1cmw9aHR0cHMlM0ElMkYlMkZzdGF0JTJFZXRoeiUyRWNoJTJGbWFpbG1hbiUyRmxpc3RpbmZvJTJGci1oZWxw
> >> >
> >> PLEASE do read the posting guide
> >> http://www.R-project.org/posting-guide.html<
> >>
http://mx2.njhealth.org:32224/?dmVyPTEuMDAxJiZlMTkwYmMwMzFlNjk4ZTAzNz01RDcyOEQwN18yMjk2OF8zOTk2XzEmJmFkYTkxMWRkMWRhZTFkNz0xMjMzJiZ1cmw9aHR0cCUzQSUyRiUyRnd3dyUyRVItcHJvamVjdCUyRW9yZyUyRnBvc3RpbmctZ3VpZGUlMkVodG1s
> >> >
> >> and provide commented, minimal, self-contained, reproducible
code.
> >>
> >> [[alternative HTML version deleted]]
> >>
> >> ______________________________________________
> >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and
more, see
> >> https://stat.ethz.ch/mailman/listinfo/r-help
> >> PLEASE do read the posting guide
> >> http://www.R-project.org/posting-guide.html
> >> and provide commented, minimal, self-contained, reproducible
code.
> >>
> >
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
______________________________________________
R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
NOTICE: This email message is for the sole use of the intended recipient(s) and
may contain confidential and privileged information. Any unauthorized review,
use, disclosure or distribution is prohibited. If you are not the intended
recipient, please contact the sender by reply email and destroy all copies of
the original message.