#const someFlag = true
#const anotherFlag = false
#const someOtherFlag = someFlag

#if FeatureA
#else if FeatureB
#else
#end if

#error Your device cannot support this feature.

----------------------------------------------------

[
	["directive-statement", [
		["directive", "#const"],
		["expression", [
			" someFlag ",
			["operator", "="],
			["boolean", "true"]
		]]
	]],
	["directive-statement", [
		["directive", "#const"],
		["expression", [
			" anotherFlag ",
			["operator", "="],
			["boolean", "false"]
		]]
	]],
	["directive-statement", [
		["directive", "#const"],
		["expression", [
			" someOtherFlag ",
			["operator", "="],
			" someFlag"
		]]
	]],

	["directive-statement", [
		["directive", "#if"],
		["expression", [
			" FeatureA"
		]]
	]],
	["directive-statement", [
		["directive", "#else if"],
		["expression", [
			" FeatureB"
		]]
	]],
	["directive-statement", [
		["directive", "#else"]
	]],
	["directive-statement", [
		["directive", "#end if"]
	]],

	["directive-statement", [
		["directive", "#error"],
		["error-message", " Your device cannot support this feature."]
	]]
]

----------------------------------------------------

Checks for directives (conditional compilation).
