Echo the expression. Useful for showing informational messages. Multiple lines can be separated by \n. {expr} can either be a quoted string, or any expression which can be fed to eval() like 4+5. You can also view the source code of objects and functions if the return value of {expr} is an object or function.
Echo the expression as an error message. Just like :echo but echoes the result highlighted as ErrorMsg and saves it to the message history.
Echo the expression as an informational message. Just like :echo but also saves the message in the message history.
Execute the string that results from the evaluation of {expr} as an Ex command. Example: :execute "source " + io.getRCFile().path sources the appropriate RC file.
Note: Unlike Vim this currently only supports a single argument.
Run any JavaScript command through eval(). Acts as a JavaScript interpreter by passing the argument to eval(). :javascript alert(Hello world) shows a dialog box with the text "Hello world". :javascript <<EOF reads all the lines until a line starting with "EOF" is found, and interpret them with the JavaScript eval() function.
The special version :javascript! opens the JavaScript console of Swiftweasel.
<Tab> completion is available for :javascript cmd (but not yet for the :js <<EOF multiline widget). Be aware that Vimperator needs to run {cmd} through eval() to get the completions, which could have unwanted side effects.
Sets or lists a variable. Sets the variable {var-name} to the value of the expression {expr1}. If no expression is given, the value of the variable is displayed. Without arguments, displays a list of all variables.