Returns true if the string contains only Binary digits

assert "1101100".is_bin  == true
assert "1101020".is_bin  == false

Property definitions

core $ Text :: is_bin
	# Returns `true` if the string contains only Binary digits
	#
	# ~~~
	# assert "1101100".is_bin  == true
	# assert "1101020".is_bin  == false
	# ~~~
	fun is_bin: Bool do
		for i in chars do if i != '0' and i != '1' then return false
		return true
	end
lib/core/text/abstract_text.nit:393,2--402,4