Counter and Theme Toggle - Crystal Typing CST Test

Counter and Theme Toggle — Crystal Code

Demonstrates a simple counter with theme toggling using Crystal variables and console output.

count = 0
is_dark = false

def update_ui(count, is_dark)
	puts "Counter: #{count}"
	puts "Theme: #{is_dark ? "Dark" : "Light"}"
end

def increment(count, is_dark)
	count += 1
	update_ui(count, is_dark)
	count
end

def decrement(count, is_dark)
	count -= 1
	update_ui(count, is_dark)
	count
end

def reset(count, is_dark)
	count = 0
	update_ui(count, is_dark)
	count
end

def toggle_theme(is_dark)
	is_dark = !is_dark
	update_ui(count, is_dark)
	is_dark
end

# Simulate actions
update_ui(count, is_dark)
count = increment(count, is_dark)
count = increment(count, is_dark)
is_dark = toggle_theme(is_dark)
count = decrement(count, is_dark)
count = reset(count, is_dark)

Crystal Language Guide

Crystal is a modern, statically typed, compiled programming language with syntax heavily inspired by Ruby. It aims to combine the efficiency and speed of compiled languages with the readability and productivity of Ruby, supporting type inference, concurrency, and high-performance applications.

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