reduce code duplication in app-update.sml by using higher order function

This commit is contained in:
2024-10-25 21:10:53 +01:00
parent a198840961
commit 39e867bd35
2 changed files with 22 additions and 177 deletions

View File

@@ -19,13 +19,15 @@ struct
(newApp, drawMsg) (newApp, drawMsg)
end end
fun moveRight (app: app_type) = fun moveBackward (app: app_type, fMove) =
let let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
(* move LineGap to cursorIdx, which is necessary for finding newCursorIdx *) (* move LineGap to cursorIdx, which is necessary for finding newCursorIdx *)
val buffer = LineGap.goToIdx (cursorIdx, buffer) val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.viL (buffer, cursorIdx) val cursorIdx = fMove (buffer, cursorIdx)
(* todo: get new startLine if cursor has moved out of screen *)
(* move LineGap to first line displayed on screen, and build new text *) (* move LineGap to first line displayed on screen, and build new text *)
val buffer = LineGap.goToLine (startLine, buffer) val buffer = LineGap.goToLine (startLine, buffer)
@@ -37,13 +39,17 @@ struct
(newApp, drawMsg) (newApp, drawMsg)
end end
fun moveLeft (app: app_type) = fun moveFowrards (app: app_type, fMove) =
let let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
(* move LineGap to cursorIdx, which is necessary for finding newCursorIdx *)
val buffer = LineGap.goToIdx (cursorIdx, buffer) val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.viH (buffer, cursorIdx) val cursorIdx = fMove (buffer, cursorIdx)
(* todo: get new startLine if cursor has moved out of screen *)
(* move LineGap to first line displayed on screen, and build new text *)
val buffer = LineGap.goToLine (startLine, buffer) val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight) (startLine, cursorIdx, buffer, windowWidth, windowHeight)
@@ -53,181 +59,20 @@ struct
(newApp, drawMsg) (newApp, drawMsg)
end end
fun moveDown (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.viJ (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun moveUp (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.viK (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun moveToLineStart (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.vi0 (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun moveToLineEnd (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.viDlr (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun nextWord (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.nextWord (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun nextWORD (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.nextWORD (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun prevWord (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.prevWord (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun prevWORD (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.prevWORD (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun endOfWord (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.endOfWord (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun endOfWORD (app: app_type) =
let
val {buffer, windowWidth, windowHeight, startLine, cursorIdx, ...} = app
val buffer = LineGap.goToIdx (cursorIdx, buffer)
val cursorIdx = Cursor.endOfWORD (buffer, cursorIdx)
val buffer = LineGap.goToLine (startLine, buffer)
val drawMsg = TextBuilder.build
(startLine, cursorIdx, buffer, windowWidth, windowHeight)
val newApp = AppWith.bufferAndCursorIdx (app, buffer, cursorIdx)
in
(newApp, drawMsg)
end
fun handleChr (app: app_type, chr) = fun handleChr (app: app_type, chr) =
case chr of case chr of
#"h" => moveLeft app #"h" => moveBackward (app, Cursor.viH)
| #"j" => moveDown app | #"j" => moveFowrards (app, Cursor.viJ)
| #"k" => moveUp app | #"k" => moveBackward (app, Cursor.viK)
| #"l" => moveRight app | #"l" => moveFowrards (app, Cursor.viL)
| #"0" => moveToLineStart app | #"0" => moveBackward (app, Cursor.vi0)
| #"$" => moveToLineEnd app | #"$" => moveFowrards (app, Cursor.viDlr)
| #"w" => nextWord app | #"w" => moveFowrards (app, Cursor.nextWord)
| #"W" => nextWORD app | #"W" => moveFowrards (app, Cursor.nextWORD)
| #"b" => prevWord app | #"b" => moveBackward (app, Cursor.prevWord)
| #"B" => prevWORD app | #"B" => moveBackward (app, Cursor.prevWORD)
| #"e" => endOfWord app | #"e" => moveFowrards (app, Cursor.endOfWord)
| #"E" => endOfWORD app | #"E" => moveFowrards (app, Cursor.endOfWORD)
| _ => (app, []) | _ => (app, [])
fun update (app, msg) = fun update (app, msg) =

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