Prepend/Append

script

// Append or prepend the selected lines (or all lines) with
// text supplied by the user.

// Prepare the prompt
var p = Prompt.create();
p.title = "Append/Prepend"
p.message = "Text to add to start or end of lines."
p.addTextField("text", "", "", {placeholder: "Added text", wantsFocus: true});
p.addButton("Prepend");
p.addButton("Append");

// Define the text that's going to be edited
// If there's no selection, use the whole draft
let st, len;
if (editor.getSelectedRange()[1] > 0) { // use selected lines
	[st, len] = editor.getSelectedLineRange();
}
else { // use full text
	[st, len] = [0, editor.getText().length];
}
let lnText = editor.getTextInRange(st, len);
if (lnText.endsWith("\n")) {
	lnText = lnText.slice(0, -1);
	len -= 1;
}

// Get the text to be added from the user
var didSelect = p.show();

if (didSelect) {
	// Edit a copy of the chosen text
	var addText = p.fieldValues["text"];
	var lines = lnText.split('\n');
	var edited = [];
	
	if (p.buttonPressed == "Prepend") {
		lines.forEach(line => edited.push(addText + line));
	}
	else {
		lines.forEach(line => edited.push(line + addText));
	}
	
	// Replace the text in the editor
	editor.setTextInRange(st, len, edited.join('\n'));
}