structure NormalMode = struct (* parsing functions, deciding what to do while we are in normal mode *) open AppType open InputMsg fun getNumLength (pos, str) = if pos = String.size str then pos else let val chr = String.sub (str, pos) in if Char.isDigit chr then getNumLength (pos + 1, str) else pos end fun appendChr (app: app_type, chr, str) = let val str = str ^ Char.toString chr val mode = NORMAL_MODE str in AppWith.mode (app, mode, []) end fun parseMoveToChr (count, app, fMove, chrCmd) = NormalMove.moveToChr (app, count, fMove, chrCmd) fun parseGo (count, app, chrCmd) = case chrCmd of #"e" => MoveToEndOfPrevWord.move (app, count) | #"E" => MoveToEndOfPrevWORD.move (app, count) | #"g" => NormalMove.moveToStart app | _ => Finish.clearMode app fun parseChr (app: app_type, count, chr, str) = case chr of #"h" => MoveViH.move (app, count) | #"j" => MoveViJ.move (app, count) | #"k" => MoveViK.move (app, count) | #"l" => MoveViL.move (app, count) | #"w" => MoveToNextWord.move (app, count) | #"W" => MoveToNextWORD.move (app, count) | #"b" => MoveToPrevWord.move (app, count) | #"B" => MoveToPrevWORD.move (app, count) | #"e" => MoveToEndOfWord.move (app, count) | #"E" => MoveToEndOfWORD.move (app, count) | #"n" => NormalMove.moveToNextMatch (app, count) | #"N" => NormalMove.moveToPrevMatch (app, count) | #"z" => Finish.centreToCursor app (* can only move to start or end of line once * so hardcode count as 1 *) | #"0" => (* 0 is a bit of a special case. * If 0 is pressed without any preceding characters, * then it should move cursor to the start of the line. * However, if a number was pressed previously before 0 was, * then this means user is entering a count. * In that case, we append 0 to the string. *) if String.size str > 0 then let val lastChr = String.sub (str, String.size str - 1) in if Char.isDigit lastChr then let val chr = Char.toString chr val str = str ^ chr val mode = NORMAL_MODE str in AppWith.mode (app, mode, []) end else MoveToStartOfLine.move (app, 1) end else MoveToStartOfLine.move (app, 1) | #"$" => MoveToEndOfLine.move (app, 1) | #"^" => NormalMove.firstNonSpaceChr app | #"G" => (* if str has a size larger than 0, * interpret as "go to line" command; * else, interpret as a command to move to end *) if String.size str = 0 then NormalMove.moveToEnd app else NormalMove.moveToLine (app, count - 1) | #"%" => NormalMove.moveToMatchingPair app | #"x" => NormalDelete.removeChr (app, count) (* multi-char commands which can be appended *) | #"t" => appendChr (app, chr, str) | #"T" => appendChr (app, chr, str) | #"y" => appendChr (app, chr, str) | #"d" => appendChr (app, chr, str) | #"f" => appendChr (app, chr, str) | #"F" => appendChr (app, chr, str) | #"g" => appendChr (app, chr, str) | #"c" => appendChr (app, chr, str) | _ => (* user may be entering a cmd with more than one chr * such as "2dw" to delete two word * so add current chr to mode, and save it in the app state *) let val str = if Char.isDigit chr then str ^ Char.toString chr else "" val mode = NORMAL_MODE str in AppWith.mode (app, mode, []) end fun parseDeleteInside (app, chr) = case chr of #"w" => NormalDelete.deleteInsideWord app | #"W" => NormalDelete.deleteInsideWORD app | #"(" => NormalDelete.deleteInsideChrOpen (app, chr) | #"[" => NormalDelete.deleteInsideChrOpen (app, chr) | #"{" => NormalDelete.deleteInsideChrOpen (app, chr) | #"<" => NormalDelete.deleteInsideChrOpen (app, chr) | #")" => NormalDelete.deleteInsideChrClose (app, chr) | #"]" => NormalDelete.deleteInsideChrClose (app, chr) | #"}" => NormalDelete.deleteInsideChrClose (app, chr) | #">" => NormalDelete.deleteInsideChrClose (app, chr) | _ => Finish.clearMode app fun parseDeleteAround (app, chr) = case chr of #"(" => NormalDelete.deleteInsideChrOpen (app, chr) | #"[" => NormalDelete.deleteInsideChrOpen (app, chr) | #"{" => NormalDelete.deleteInsideChrOpen (app, chr) | #"<" => NormalDelete.deleteInsideChrOpen (app, chr) | #")" => NormalDelete.deleteAroundChrClose (app, chr) | #"]" => NormalDelete.deleteAroundChrClose (app, chr) | #"}" => NormalDelete.deleteAroundChrClose (app, chr) | #">" => NormalDelete.deleteAroundChrClose (app, chr) | _ => Finish.clearMode app fun parseDeleteTerminal (str, count, app, chrCmd) = case chrCmd of (* terminal commands: require no input after *) #"h" => NormalDelete.delete (app, count, Cursor.viH) | #"l" => NormalDelete.delete (app, count, Cursor.viL) (* vi's 'j' and 'k' commands move up or down a column * but 'dj' or 'dk' delete whole lines * so their implementation differs from * other cursor motions *) | #"j" => NormalDelete.deleteLine (app, count + 1) | #"k" => NormalDelete.deleteLineBack (app, count) | #"w" => NormalDelete.deleteByDfa (app, count, Cursor.nextWord) | #"W" => NormalDelete.deleteByDfa (app, count, Cursor.nextWORD) | #"b" => NormalDelete.deleteByDfa (app, count, Cursor.prevWord) | #"B" => NormalDelete.deleteByDfa (app, count, Cursor.prevWORD) | #"e" => NormalDelete.deleteByDfa (app, count, Cursor.endOfWordForDelete) | #"E" => NormalDelete.deleteByDfa (app, count, Cursor.endOfWORDForDelete) | #"0" => NormalDelete.delete (app, 1, Cursor.vi0) | #"$" => NormalDelete.deleteToEndOfLine app | #"^" => NormalDelete.deleteToFirstNonSpaceChr app | #"d" => NormalDelete.deleteLine (app, count) | #"n" => NormalDelete.deleteToNextMatch (app, count) | #"N" => NormalDelete.deleteToPrevMatch (app, count) | #"%" => NormalDelete.deletePair app (* non-terminal commands which require appending chr *) | #"t" => appendChr (app, chrCmd, str) | #"T" => appendChr (app, chrCmd, str) | #"f" => appendChr (app, chrCmd, str) | #"F" => appendChr (app, chrCmd, str) | #"g" => appendChr (app, chrCmd, str) | #"i" => appendChr (app, chrCmd, str) | #"a" => appendChr (app, chrCmd, str) (* invalid command: reset mode *) | _ => Finish.clearMode app fun parseDeleteGo (app, count, chrCmd) = case chrCmd of #"e" => NormalDelete.deleteByDfa (app, count, Cursor.endOfPrevWord) | #"E" => NormalDelete.deleteByDfa (app, count, Cursor.endOfPrevWORD) | #"g" => NormalDelete.deleteToStart app | _ => Finish.clearMode app fun parseDelete (strPos, str, count, app, chrCmd) = if strPos = String.size str - 1 then parseDeleteTerminal (str, count, app, chrCmd) else (* have to continue parsing string *) case String.sub (str, strPos + 1) of #"t" => NormalDelete.deleteToChr (app, 1, Cursor.tillNextChr, op+, chrCmd) | #"T" => NormalDelete.deleteToChr (app, 1, Cursor.tillPrevChr, op-, chrCmd) | #"f" => NormalDelete.deleteToChr (app, count, Cursor.toNextChr, op+, chrCmd) | #"F" => NormalDelete.deleteToChr (app, count, Cursor.toPrevChr, op-, chrCmd) | #"g" => parseDeleteGo (app, count, chrCmd) | #"i" => parseDeleteInside (app, chrCmd) | #"a" => parseDeleteAround (app, chrCmd) | _ => Finish.clearMode app (* useful reference as list of non-terminal commands *) fun parseAfterCount (strPos, str, count, app, chrCmd) = (* we are trying to parse multi-char but non-terminal strings here. * For example, we don't want to parse 3w which is a terminal commmand * to go 3 words forwards * but we do want to parse 3d which is a non-terminal command * which can be made terminal by adding "w" or "e" at the end. * *) case String.sub (str, strPos) of #"t" => (* to just before char, forward * tillNextChr with count of 1 has same effect * as tillNextChr with any count above 1 * so just hardcode 1 *) parseMoveToChr (1, app, Cursor.tillNextChr, chrCmd) | #"T" => (* to just before chr, backward *) parseMoveToChr (1, app, Cursor.tillPrevChr, chrCmd) | #"y" => (* yank *) Finish.clearMode app | #"d" => (* delete *) parseDelete (strPos, str, count, app, chrCmd) | #"f" => (* to chr, forward *) parseMoveToChr (count, app, Cursor.toNextChr, chrCmd) | #"F" => (* to chr, backward *) parseMoveToChr (count, app, Cursor.toPrevChr, chrCmd) | #"g" => (* go *) parseGo (count, app, chrCmd) | #"c" => (* change *) Finish.clearMode app | _ => (* isn't a non-terminal cmd * this case should never happen*) Finish.clearMode app fun parseNormalModeCommand (app, str, chrCmd) = if String.size str = 0 then parseChr (app, 1, chrCmd, str) else if String.size str = 1 then case Int.fromString str of SOME count => parseChr (app, count, chrCmd, str) | NONE => parseAfterCount (0, str, 1, app, chrCmd) else let val numLength = getNumLength (0, str) val count = String.substring (str, 0, numLength) val count = case Int.fromString count of SOME x => x | NONE => 1 in if numLength = String.size str then (* reached end of str; str only contained numbers *) parseChr (app, count, chrCmd, str) else (* continue parsing. *) parseAfterCount (numLength, str, count, app, chrCmd) end fun update (app, str, msg) = case msg of CHAR_EVENT chrCmd => parseNormalModeCommand (app, str, chrCmd) | KEY_ESC => Finish.clearMode app | RESIZE_EVENT (width, height) => Finish.resizeText (app, width, height) | WITH_SEARCH_LIST searchList => Finish.withSearchList (app, searchList) end