dollar-sign

bash allows $' string ' expansion. My man bash says: Words of the form $' string ' are treated specially. The word expands to string , with backslash-escaped characters replaced as specified by the ANSI C standard. Backslash escape sequences, if present, are decoded as follows: \a alert (bell) \b backspace \e \E an escape character \f form feed \n new line \r carriage return \t horizontal tab \v vertical tab \ backslash \' single quote \" double quote \ nnn the eight-bit character whose value is the octal value nnn (one to three digits) \x HH the eight-bit character whose value is the

If I have a variable containing an unescaped dollar sign, is there any way I can echo the entire contents of the variable? For example something calls a script: ./script.sh "test1$test2" and then if I want to use the parameter it gets "truncated" like so: echo ${1} test1 Of course single-quoting the varaible name doesn't help. I can't figure out how to quote it so that I can at least escape the dollar sign myself once the script recieves the parameter. The variable is replaced before the script is run. ./script.sh 'test1$test2' The problem is that script receives "test1" in the first place and

I'm trying to escape several special characters in a given string using perl regex. It works fine for all characters except for the dollar sign. I tried the following: my %special_characters; $special_characters{"_"} = "\\_"; $special_characters{"$"} = "\\$"; $special_characters{"{"} = "\\{"; $special_characters{"}"} = "\\}"; $special_characters{"#"} = "\\#"; $special_characters{"%"} = "\\%"; $special_characters{"&"} = "\\&"; my $string = '$foobar'; foreach my $char (keys %special_characters) { $string =~ s/$char/$special_characters{$char}/g; } print $string; Try this: my %special_characters;

Possible Duplicate: Why would a javascript variable start with a dollar sign? I see people using the dollar sign in front of variables when using jQuery. Is there any reason behind this? I'm I missing something basic or is it just a common practice? It's a common reference to a jQuery wrapped object. It makes reading the code easier to know which variables are jQuery wrapped. //Item has been "cached" for later use in the script as a jQuery object. var $item = $(this); locrizak For me a common practice is this: If a variable is private I use an underscore like this: (function(){ var _foo = "bar

When you are writing slightly more complex functions I notice that $ is used a lot but I don't have a clue what it does? J. Abrahamson $ is infix "application". It's defined as ($) :: (a -> b) -> (a -> b) f $ x = f x -- or ($) f x = f x -- or ($) = id It's useful for avoiding extra parentheses: f (g x) == f $ g x . A particularly useful location for it is for a "trailing lambda body" like forM_ [1..10] $ \i -> do l <- readLine replicateM_ i $ print l compared to forM_ [1..10] (\i -> do l <- readLine replicateM_ i (print l) ) Or, trickily, it shows up sectioned sometimes when expressing "apply

I understand JavaScript closures, and I've seen this done in native JS: (function () { // all JS code here })(); But, what does adding the jQuery spice do? (function ($) { // all JS code here })(jQuery); Its a way of mapping jQuery to the $ in a way so that not all code in a page will see it. Maybe you have an existing script that uses jQuery that you like to reuse but you also use prototype that also uses $ in the same page. By wrapping any jQuery using code in that construct you redefine $ to jQuery for the contained part without coming into conflict with other code in the page. When you see