QT6 application written in nim

[Alain De Vos]

In the sweet spot between C & C++ there is the esoteric language NIM.
Drawbacks :
- Main developer has a difficult character.
- & No foundation. So companies don't welcome this language.
Good things :
- Class emulation
- Reference counting behaving like garbage collection
- Good libaries
https://nim-lang.org/docs/lib.html

Example of object orientation in NIM Language, code is self declarative.

type Warrior = object
  name: string
  hp: int

# "Constructor" - returns the object by value on the stack
proc newWarrior(name: string, hp: int): Warrior =
  Warrior(name: name, hp: hp)

# Member function emulation
proc takeDamage(self: var Warrior, amount: int) =
  self.hp -= amount
  echo self.name, " took damage! HP is now: ", self.hp

# Usage
var hero = newWarrior("Arthur", 100) # Created on stack
hero.takeDamage(20)                  # Method syntax

---------------------------------------------------------------------------------------------------------------------------
Example of a QT6 application with callback functions :

cat test.nim

import std/strformat, seaqt/[qapplication, qpushbutton, qlineedit, qlabel, qvboxlayout, qwidget]

let
  _ = QApplication.create()
  window = QWidget.create()
  layout = QVBoxLayout.create(window)
 
  label = QLabel.create("Ready...")
  edit = QLineEdit.create()
  btn = QPushButton.create("Hello seaqt!")

layout.addWidget(label)
layout.addWidget(edit)
layout.addWidget(btn)

var counter = 0

btn.onPressed(
  proc() {.closure.} =
    counter += 1
    btn.setText(&"Clicks: {counter}")
)

# Fix: Match the signature 'openArray[char]'
edit.onTextChanged(
  proc(text: openArray[char]) {.closure.} =
    # Convert openArray[char] to string for the label
    label.setText("Input: " & $text)
)

window.setMinimumSize(320, 200)
window.show()

quit QApplication.exec().int

Script to install library & compile :

nimble install https://github.com/seaqt/nim-seaqt.git@#qt-6.4
nim cpp --run --passC:-fPIC ./test.nim

As you see this is rather easy & straightforward.

 

[Alain De Vos]

[Later i'll come back with dlang, must figure out how it works with QT6]