Situation.. I have two tags defined, then I try to output them to the console. What comes out seems to be similar to an array, but I'd like to remove the formatting and just have the actual words outputted.
Here's what I currently have:
[Tags] ready ver10
Log To Console \n#{TEST TAGS}
And the result is
['ready', 'ver10']
So, how would I chuck the [', the ', ' and the '], thus only retaining the words ready and ver10?
Note: I was getting [u'ready', u'ver10'] - but once I got some advice to make sure I was running Python3 RobotFramework - after uninstalling robotframework via pip, and now only having robotframework installed via pip3, the u has vanished. That's great!
There are several ways to do it. For example, you could use a loop, or you could convert the list to a string before calling log to console
Using a loop.
Since the data is a list, it's easy to iterate over the list:
FOR ${tag} IN #{Test Tags}
log to console ${tag}
END
Converting to a string
You can use the evaluate keyword to convert the list to a string of values separated by a newline. Note: you have to use two backslashes in the call to evaluate since both robot and python use the backslash as an escape character. So, the first backslash escapes the second so that python will see \n and convert it to a newline.
${tags}= evaluate "\\n".join($test_tags)
log to console \n${tags}
Related
I've seen that since 4.0.0, R supports raw strings using the syntax r"(...)". Thus, I could do:
r"(C:\THIS\IS\MY\PATH\TO\FILE.CSV)"
#> [1] "C:\\THIS\\IS\\MY\\PATH\\TO\\FILE.CSV"
While this is great, I can't figure out how to make this work with a variable, or better yet with a function. See this comment which I believe is asking the same question.
This one can't even be evaluated:
construct_path <- function(my_path) {
r"my_path"
}
Error: malformed raw string literal at line 2
}
Error: unexpected '}' in "}"
Nor this attempt:
construct_path_2 <- function(my_path) {
paste0(r, my_path)
}
construct_path_2("(C:\THIS\IS\MY\PATH\TO\FILE.CSV)")
Error: '\T' is an unrecognized escape in character string starting ""(C:\T"
Desired output
# pseudo-code
my_path <- "C:\THIS\IS\MY\PATH\TO\FILE.CSV"
construct_path(path)
#> [1] "C:\\THIS\\IS\\MY\\PATH\\TO\\FILE.CSV"
EDIT
In light of #KU99's comment, I want to add the context to the problem. I'm writing an R script to be run from command-line using WIndows's CMD and Rscript. I want to let the user who executes my R script to provide an argument where they want the script's output to be written to. And since Windows's CMD accepts paths in the format of C:\THIS\IS\MY\PATH\TO, then I want to be consistent with that format as the input to my R script. So ultimately I want to take that path input and convert it to a path format that is easy to work with inside R. I thought that the r"()" thing could be a proper solution.
I think you're getting confused about what the string literal syntax does. It just says "don't try to escape any of the following characters". For external inputs like text input or files, none of this matters.
For example, if you run this code
path <- readline("> enter path: ")
You will get this prompt:
> enter path:
and if you type in your (unescaped) path:
> enter path: C:\Windows\Dir
You get no error, and your variable is stored appropriately:
path
#> [1] "C:\\Windows\\Dir"
This is not in any special format that R uses, it is plain text. The backslashes are printed in this way to avoid ambiguity but they are "really" just single backslashes, as you can see by doing
cat(path)
#> C:\Windows\Dir
The string literal syntax is only useful for shortening what you need to type. There would be no point in trying to get it to do anything else, and we need to remember that it is a feature of the R interpreter - it is not a function nor is there any way to get R to use the string literal syntax dynamically in the way you are attempting. Even if you could, it would be a long way for a shortcut.
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 would like to give a more informative error message when users of my R functions supply a string with an unrecognized escape
my_string <- "sql\sql"
# Error: '\s' is an unrecognized escape in character string starting ""sql\s"
Something like this would be ideal.
my_string <- "sql\sql"
# Error: my_string contains an unrecognized escape. Try sql\\sql with double backslashes instead.
I have tried an if statement that looks for single backslashes
if (stringr::str_detect("sql\sql", "\")) stop("my error message")
but I get the same error.
Almost all of my users are Windows users running R 3.3 and up.
Code execution in R happens in two phases. First, R takes the raw string you enter and parses that into commands that can be run; then, R actually runs those commands. The parsing step makes sure what you've written actually makes sense as code. If it doesn't make any sense, then R can't even turn it into anything it can attempt to run.
The error message you are getting about the unrecognized escape sequence is happening at the parsing stage. That means R isn't really even attempting to execute the command, it just straight up can't understand what you are saying. There is no way to catch in error like this in code because there's no user code that's running at that point.
So if you are counting on your users writing code like my_string <- "something", then they need to write valid code. They can't change how strings are encoded or what the assignment operator looks like or how variables can be named. They also can't type !my_string! <=== %something% because R can't parse that either. R can't parse my_string <- "sql\sql" but it can parse my_string <- "sql\\sql" (slashes much be escaped in string literals). If they are not savy users, you might want to consider providing an alternative interface that can sanitize user input before trying to run it as code. Maybe make a shiny front end or have users pass arguments to your scripts via command line parameters.
If you're capturing your user input correctly, for a string input of\, R will store that in my_string as \\.
readline()
\
[1] "\\"
readline()
sql\sql
[1] "sql\\sql"
That means internally in R:
my_string <- "sql\\sql"
However
cat(my_string)
sql\sql
To check the input, you need to escape each escape, because you're looking for \\
stringr::str_detect(my_string, "\\\\")
Which returns TRUE if the input string is sql\sql. So the full line is:
if (stringr::str_detect("sql\\sql", "\\\\")) stop("my error message")
I have a CSV file and I want to remove the all line feeds (LF or \n) which are all coming in between the double quotes alone.
Can you please provide me an Unix script to perform the above task. I have given the input and expected output below.
Input :
No,Status,Date
1,"Success
Error",1/15/2018
2,"Success
Error
NA",2/15/2018
3,"Success
Error",3/15/2018
Expected output:
No,Status,Date
1,"Success Error",1/15/2018
2,"Success Error NA",2/15/2018
3,"Success Error",3/15/2018
I can't write everything for you, as I am not sure about your system as well as which bash version that is running on it. But here are a couple of suggestions that you might want to consider.
https://www.unix.com/shell-programming-and-scripting/31021-removing-line-breaks-shell-variable.html
https://www.unix.com/shell-programming-and-scripting/19484-remove-line-feeds.html
How to remove carriage return from a string in Bash
https://unix.stackexchange.com/questions/57124/remove-newline-from-unix-variable
Remove line breaks in Bourne Shell from variable
https://unix.stackexchange.com/questions/254644/how-do-i-remove-newline-character-at-the-end-of-file
https://serverfault.com/questions/391360/remove-line-break-using-awk
I've searched through several answers here and through Google, but I'm still not sure what's going wrong with my prompt.
According to the documentation I've read, this should work
setopt prompt_subst
autoload -U colors && colors
PROMPT="%{[00m[38;5;245m%}test %D%{[00m%}"
My prompt is the following, however:
[00m[38;5;245mtest 15-07-01[00m
Note that the date expansion actually worked, so prompt substitution is working. The ZSH man pages for prompt expansion states that %{...%} should be treated as a raw escape code, but that doesn't seem to be happening. Passing that string to print -P also results in the output above. I've found example prompts on the Internet for ZSH that also seem to indicate that the above syntax should work. See this for one example - the $FG and $FX arrays are populated with escape codes and are defined here. I've tried this example directly by merging both the files above, adding setopt prompt_subst to the beginning just to make sure it's set, then sourcing it and the prompt is a mess of escape codes.
The following works
setopt prompt_subst
autoload -U colors && colors
PROMPT=$'%{\e[00m\e[38;5;245m%}test %D%{\e[00m%}'
I get the expected result of test 15-07-01 in the proper color.
I've tested this on ZSH 5.0.5 in OSX Yosimite, 5.0.7 from MacPorts, and 4.3.17 on Debian, with the same results. I know I have provided a valid solution to my own problem here with the working example, but I'm wondering why the first syntax isn't working as it seems it should.
I think this all has to do with the timeless and perennial problem of escaping. It's worth reminding ourselves what escaping means, briefly: an escape character is an indicator to the computer that what follows should not be output literally.
So there are 2 escaping issues with:
PROMPT="%{[00m[38;5;245m%}test %D%{[00m%}"
Firstly, the colour escape sequences (eg; [00m) should all start with the control character like so \e[00m. You may have also seen it written as ^[00m and \003[00m. What I suspect has happened is one of the variations has suffered the common fate of being inadvertently escaped by either the copy/paste of the author or the website's framework stack, whether that be somewhere in a database, HTTP rendering or JS parsing. The control character (ie, ^, \e or \003), as you probably know, does not have a literal representation, say if you press it on the keyboard. That's why a web stack might decide to not display anything if it sees it in a string. So let's correct that now:
PROMPT="%{\e[00m\e[38;5;245m%}test %D%{\e[00m%}"
This actually nicely segues into the next escaping issue. Somewhat comically \e[ is actually a representation of ESC, it is therefore in itself an escape sequence marker that, yes, is in turn escaped by \. It's a riff on the old \\\\\\\\\\ sort of joke. Now, significantly, we must be clear on the difference between the escape expressions for the terminal and the string substitutions of the prompt, in pseudo code:
PROMPT="%{terminal colour stuff%}test %D%{terminal colour stuff%}"
Now what I suspect is happening, though I can't find any documentation to prove it, is that once ZSH has done its substitutions, or indeed during the substitution process, all literal characters, regardless of escape significations, are promoted to real characters¹. To yet further the farce, this promotion is likely done by escaping all the escape characters. For example if you actually want to print '\e' on the command line, you have to do echo "\\\e". So to overcome this issue, we just need to make sure the 'terminal colour stuff' escape sequences get evaluated before being assigned to PROMPT and that can be done simply with the $'' pattern, like so:
PROMPT=$'%{\e[00m\e[38;5;245m%}test %D%{\e[00m%}'
Note that $'' is of the same ilk as $() and ${}, except that its only function is to interpret escape sequences.
[1] My suspicion for this is based on the fact that you can actually do something like the following:
PROMPT='$(date)'
where $(date) serves the same purpose as %D, by printing a live version of the date for every new prompt output to the screen. What this specific examples serves to demonstrate is that the PROMPT variable should really be thought of as storage for a mini script, not a string (though admittedly there is overlap between the 2 concepts and thus stems confusion). Therefore, as a script, the string is first evaluated and then printed. I haven't looked at ZSH's prompt rendering code, but I assume such evaluation would benefit from native use of escape sequences. For example what if you wanted to pass an escape sequence as an argument to a command (a command that gets run for every prompt render) in the prompt? For example the following is functionally identical to the prompt discussed above:
PROMPT='%{$(print "\e[00m\e[38;5;245m")%}test $(date)%{$(print "\e[00m")%}'
The escape sequences are stored literally and only interpreted at the moment of each prompt rendering.