Learning to wren 1

2021-04-27

¶Wren is a small, fast, class-based concurrent scripting language.

¶注釋

// /*  */

¶保留字

1 2	as break class construct continue else false for foreign if import in is null return static super this true var while

¶控制臺輸出

1	System.print("hi")

¶字符串

¶普通

"test"

¶强制

1
2
3

"""
Hello world
"""

¶範圍

¶全包含

3..8

¶半包含

4...6

¶列表

var trees = ["cedar", "birch", "oak", "willow"]
trees[0..-1]
trees.count
matrix[3, 5]

¶映射

{
  "maple":  "Sugar Maple (Acer Saccharum)",
  "larch":  "Alpine Larch (Larix Lyallii)",
  "oak":    "Red Oak (Quercus Rubra)",
  "fir":    "Fraser Fir (Abies Fraseri)"
}

¶循環

1
2
3

for (i in 1..100) {
  System.print(i)
}

¶函數

var sayHello = Fn.new { System.print("hello") }
sayHello.call() //> hello
link.onClick {|button|
  System.print("I was clicked by button %(button)")
}
var onEvent = Fn.new {|button|
  System.print("clicked by button %(button)")
}

¶過濾

1	var filtered = list.where {\|value\| value > 3 }