Inline `Array.from`

from.macro.sjs

macro inline_from {
	rule { ($constructor:expr, $list:expr, function ($value:ident, $index:ident, $ref:ident) {
		$return:expr
	}, $context:expr) } => {
		(function (constructor, ref) {
			var length = ref.length, res = new constructor(length);
			
			for (var $index = 0; $index < length; $index += 1) {
				var $value = ref[$index];
				
				res[$index] = $return;
			}
 
			return res;
		}.call($context, $constructor, $list));
	}
}

let from = macro {
	rule infix { $symbol:ident (.) ... $constructor:ident . | ($list:expr, () => $return:expr) } => {
		inline_from($symbol (.) ... $constructor, $list, function (value, index, ref) { $return }, this)
	}
	rule infix { $constructor:expr . | ($list:expr, () => $return:expr) } => {
		inline_from($constructor, $list, function (value, index, ref) { $return }, this)
	}
	rule infix { $symbol:ident (.) ... $constructor:ident . | ($list:expr, $value:ident => $return:expr) } => {
		inline_from($symbol (.) ... $constructor, $list, function ($value, index, ref) { $return }, this)
	}
	rule infix { $constructor:expr . | ($list:expr, $value:ident => $return:expr) } => {
		inline_from($constructor, $list, function ($value, index, ref) { $return }, this)
	}
	rule infix { $symbol:ident (.) ... $constructor:ident . | ($list:expr, ($value:ident) => $return:expr) } => {
		inline_from($symbol (.) ... $constructor, $list, function ($value, index, ref) { $return }, this)
	}
	rule infix { $constructor:ident . | ($list:expr, ($value:ident) => $return:expr) } => {
		inline_from($constructor, $list, function ($value, index, ref) { $return }, this)
	}
	rule infix { $symbol:ident (.) ... $constructor:ident . | ($list:expr, ($value:ident, $index:ident) => $return:expr) } => {
		inline_from($symbol (.) ... $constructor, $list, function ($value, $index, ref) { $return }, this)
	}
	rule infix { $constructor:expr . | ($list:expr, ($value:ident, $index:ident) => $return:expr) } => {
		inline_from($constructor, $list, function ($value, $index, ref) { $return }, this)
	}
	rule { $rest ... } => { from $rest ... }
}

export from;