colon

I was wondering: what's the difference between writing a selector name with no colon @selector(mySelector) , or @selector(mySelector:) with the colon? As in: UIBarButtonItem *addButton = [[UIBarButtonItem alloc]initWith... target:self action:@selector(addAction:)]; I can't find another example without the colon, but I'm quite sure I have already seen some of them. The colon is needed after the method's name if and only if the method takes an argument. No function parameters: -(void)addAction {} // Use ...@selector(addAction)... Has parameter: -(void)addAction:(id)info {} // Use ...@selector

I'm getting terribly confused by the colon notation used when defining/calling Lua functions. I thought I'd got my head round it until I saw this piece of code: function string.PatternSafe( str ) return ( str:gsub( ".", pattern_escape_replacements ) ); end function string.Trim( s, char ) if char then char = char:PatternSafe() else char = "%s" end return string.match( s, "^" .. char .. "*(.-)" .. char .. "*$" ) or s end What's confusing me here is that string.PatternSafe() doesn't reference 'self' anywhere, yet the code seems to work. I've also seen some scripts that use colon notation when

This question already has answers here : Explanation of colon operator in “: ${foo=value}” (2 answers) What is the purpose of the : (colon) GNU Bash builtin? (11 answers) Closed 4 years ago . I could not find any documentation that would explain the syntax below. What does it do inside a bash script? Is it a test? : ${foo:=bar}; export foo The : command is the null utility : This utility shall only expand command arguments. It is used when a command is needed, as in the then condition of an if command, but nothing is to be done by the command. Also Bourne Shell Builtins : Do nothing beyond

This is part of the wordpress code and I don't understand it: if ( is_404() && $template = get_404_template() ) : elseif ( is_search() && $template = get_search_template() ) : elseif ( is_tax() && $template = get_taxonomy_template() ) : elseif ( is_front_page() && $template = get_front_page_template() ) : elseif ( is_home() && $template = get_home_template() ) : elseif ( is_attachment() && $template = get_attachment_template() ) : remove_filter('the_content', 'prepend_attachment'); elseif ( is_single() && $template = get_single_template() ) : elseif ( is_page() && $template = get_page_template

Please pardon my ignorance; I'm new to Git and not sure where better to look for an answer, but what's the purpose of the colon after 'example.com' in the following url (which points to a git repository on my mediatemple server)? git remote add repo_name ssh://serveradmin%example.com@example.com:/home/45678/domains/git.example.com/html/example.git This syntax is actually wrong, but it's a bit like the scp -style syntax that you can use in git URLs, where it separates the hostname from the path on that host. Your options for specifying git URLs are listed in the git clone documentation . In

What does the syntax, colons preceding variable in Common Lisp, mean? I've seen programs with such, and I'll present some sample code here, out of a large set of functions. (defun expand (successorf node) (mapcar (lambda (action-state-cost) (let ((action (car action-state-cost)) (state (cadr action-state-cost)) (cost (caddr action-state-cost))) (make-node :state state :parent node :action action :path-cost (+ (node-path-cost node) cost) :depth (1+ (node-depth node))) )) (funcall successorf (node-state node)) )) They're not variables, actually; those are keywords. They're a special kind of