September 9, 2012 at 11:11 AM by Dr. Drang
As before, virtually all the credit goes to Nathan. He extended and cleaned up my initial ideas on how to handle multi-word commands and keywords—things like
display dialog and
choose from list, which AppleScript is littered with—putting them in a form that both more consistent with the rest of Highlight.js and easier to work with in a CSS file. My only contribution has been a simple definition that tries to distinguish between the use of the word
return as a command and its use as a constant.
Here’s a brief test suite that shows the features (and a couple of bugs):
applescript: -- multi-word commands do shell script "date" display dialog "Does this work?" -- multi-word constant set text item delimiters to "|" -- types and properties tell application "iTunes" to get current selection get character 5 from "abcdefghij" -- multi-word keyword (greater than) if 5 is greater than 4 then set thing to 6 end if -- "return" as a constant set a to return & "abc" & return & "def" & linefeed & "ghi" -- "return" as a command return a -- "return" as a command and constant if 4 is less than 5 then return thing & return & a end if -- "return" inside string is properly identified set c to "abc is not a return to def" -- "return" as a constant, misidentified as a command set b to "abc" & ¬ return & "def" -- application dictionaries can redefine words tell application "BBEdit" to set show tab stops to true
The second-to-last example shows how the rule for
return can be fooled to show its use as a constant misidentified as a command.
The last example shows a feature of AppleScript that will play havoc with any syntax highlighter that isn’t itself an AppleScript interpreter: dictionaries can redefine words, even words that are part of the core of AppleScript. In this case, AppleScript’s
tab constant has been subsumed into the
show tab stops property in BBEdit’s dictionary. The highlighter knows
tab but knows nothing of
show tab stops, so the highlighting is wrong. This is the problem Hamish Sanderson (has) was talking about in his comments on my earlier post. He had some suggestions on how to get around this problem, but they’d change my workflow in ways I’m not willing to accept at the moment. I’ll live with the occasional highlighting errors.
If you want to use these definitions with Highlight.js, get a copy of either my fork or Nathan’s from GitHub. Make sure you get the “applescript” branch. In Terminal,
cd to the main directory of the repository and execute
python tools/build.py :common applescript
This will create a “packed” version of Highlight.js in the
build directory called
highlight.pack.js to your web server and add the code to your HTML that will include and call it.
The highlighting styles come through CSS. You can use one of the many styles that come with Highlight.js or use one of them as a template to create your own. To highlight certain AppleScript language features, you’ll have to include styles for the following classes that aren’t in the standard Highlight.js CSS files:
pre .propertyfor things like
pre .typefor things like
pre .commandfor things like
display dialog, and
do shell script.