The GNU project has a standard for how command line arguments should look like. However, there is no description for what to do, when an option has multiple arguments. Is there a convention for a special character to separate those arguments?
Example:
--longOption="firstArg;secondArg" -s first;second
In my case, I need to be able to specify one option multiple times, which results in creating an object multiple times with different parameters.
This must be possible:
--longOption="allArgs;for;firstObject" --longOption="args;for;second"
I guess I would also need a way to escape that separation character somehow...
Related
I work with knitr() and I wish to transform inline Latex commands like "\label" and "\ref", depending on the output target (Latex or HTML).
In order to do that, I need to (programmatically) generate valid R strings that correctly represent the backslash: for example "\label" should become "\\label". The goal would be to replace all backslashes in a text fragment with double-backslashes.
but it seems that I cannot even read these strings, let alone process them: if I define:
okstr <- function(str) "do something"
then when I call
okstr("\label")
I directly get an error "unrecognized escape sequence"
(of course, as \l is faultly)
So my question is : does anybody know a way to read strings (in R), without using the escaping mechanism ?
Yes, I know I could do it manually, but that's the point: I need to do it programmatically.
There are many questions that are close to this one, and I have spent some time browsing, but I have found none that yields a workable solution for this.
Best regards.
Inside R code, you need to adhere to R’s syntactic conventions. And since \ in strings is used as an escape character, it needs to form a valid escape sequence (and \l isn’t a valid escape sequence in R).
There is simply no way around this.
But if you are reading the string from elsewhere, e.g. using readLines, scan or any of the other file reading functions, you are already getting the correct string, and no handling is necessary.
Alternatively, if you absolutely want to write LaTeX-like commands in literal strings inside R, just use a different character for \; for instance, +. Just make sure that your function correctly handles it everywhere, and that you keep a way of getting a literal + back. Here’s a suggestion:
okstr("+label{1 ++ 2}")
The implementation of okstr then needs to replace single + by \, and double ++ by + (making the above result in \label{1 + 2}). But consider in which order this needs to happen, and how you’d like to treat more complex cases; for instance, what should the following yield: okstr("1 +++label")?
I have to use Textpad in my environment. To treat a file (on a regular basis) it is necessary to make +/- 20 replacements, some of them regex, some of them not. For most of the replacements I have defined macros (for each replacement one macro, i. e. 1:1). It is possible to "concat" macros or put replacements "in a sequence"? If it is possible: Would this sequence break, if one replacement does not find matching patters (off course, it should not break).
I'm not sure how you would "concat" them aside from recording each macro together (unless you know how to concat the files)... but as your question is about "would it work"... then I'd say yes but you would have to ensure each marco started in the right place.
I'd recommend each macro started and ended with something like Ctrl+Home to ensure a consistent starting / ending place
Is it possible to get a list of declared variables with a VimL (aka VimScript) expression? I'd like to get the same set of values that will be presented for a command using -complete=expression. The goal is to augment that list for use in a user-defined command completion function.
You can use g: as a dictionary that holds all global variables, so:
let globals = keys(g:)
will give you all the names. The same applies to the other scopes: b:, s:, w:, etc. See :help internal-variables for the complete list.
You can get something similar using keys of g:, b:, t:, w: and v: dictionaries, but beware of the following facts:
There is no equivalent to this dictionaries if you want to complete options.
Some variables like count (but not g:count or l:count), b:changedtick and, maybe, others are not present in this dictionaries.
Some vim hacker may add key ### to dictionary g:, but it won't make expression g:### valid variable name (but adding 000 there will). Though g:["###"] will be a valid expression.
I am using the Jobdepends command to get a list of jobs stating with tax_check_d_%
I need files like tax_check_d_job
but it returns
tax_check_djob
tax_check_d_job
tax_check_djob_job
how can i select only tax_check_d_job?
When used in a job filter, the _ (underscore) character is a wildcard that matches exactly one character. This explains why you are seeing the unwanted results coming back -tax_check_d_job_% is essentially the same as tax_check_d_job%.
Unfortunately I don't think there's a way around this - according to the Autosys 4.0 reference guide, the SQL ESCAPE option is not supported for wildcards.
I would suggest adding one more character onto your search criteria to filter out the unwanted results, running the command multiple times if necessary. E.g. run it with tax_check_d_job_a%, tax_check_d_job_b%, ... as necessary.
You could also use some custom code to strip out the results you don't want to see. Depending on your needs, this could be a simple as
job_depends -d -J tax_check_d_job_% | grep "tax_check_d_job_.*"
As part of a larger task performed in R run under windows, I would like to copy selected files between directories. Is it possible to give within R a command like cp patha/filea*.csv pathb (notice the wildcard, for extra spice)?
I don't think there is a direct way (shy of shelling-out), but something like the following usually works for me.
flist <- list.files("patha", "^filea.+[.]csv$", full.names = TRUE)
file.copy(flist, "pathb")
Notes:
I purposely decomposed in two steps, they can be combined.
See the regular expression: R uses true regex, and also separates the file pattern from the path, in two separate arguments.
note the ^ and $ (beg/end of string) in the regex -- this is a common gotcha, as these are implicit to wildcard-type patterns, but required with regexes (lest some file names which match the wildcard pattern but also start and/or end with additional text be selected as well).
In the Windows world, people will typically add the ignore.case = TRUE argument to list.files, in order to emulate the fact that directory searches are case insensitive with this OS.
R's glob2rx() function provides a convenient way to convert wildcard patterns to regular expressions. For example fpattern = glob2rx('filea*.csv') returns a different but equivalent regex.
You can
use system() to fire off a command as if it was on shell, incl globbing
use list.files() aka dir() to do the globbing / reg.exp matching yourself and the copy the files individually
use file.copy on individual files as shown in mjv's answer