Haxe语法支持下面的常量：
The Haxe syntax supports the following constants:
Int：一个整型（第2.1.1节），例如0，1，97121，-12， 0xFF0000 。 Float：一个浮点数（第2.1.1节），如0.0，1.，.3，-93.2 。 String：一个字符串（第10.1节），如""，“foo”，''，'bar' 。 true，false：一个布尔值 null：null值
Int: An integer (2.1.1), such as 0, 1, 97121, -12, 0xFF0000. Float: A floating point number (2.1.1), such as 0.0, 1., .3, -93.2. String: A string of characters (10.1), such as "", "foo", ’’, ’bar’. true,false: A boolean (2.1.4) value. null: The null value.
此外，内部的语法结构将标识符作为常量，可能在使用宏（第9章）时是相关的。
Furthermore, the internal syntax structure treats identifiers (5) as constants, which may be relevant when working with macros (9).
Constants are values which are immutable. These values can be used as inline variables and default values for function arguments. All constants are literals, except for argument-less enum constructors:
| Example | Type | Note |
|---|---|---|
42, 0xFF42 |
Int |
integer constant |
0.32, 3., 2.1e5 |
Float |
floating-point decimal constant |
true, false |
Bool |
boolean constant |
~/haxe/gi |
EReg |
regular expression |
null |
T |
null value for any nullable type |
"XXX", 'XXX' |
String |
string literal |
"X".code, 'X'.code |
Int |
Unicode character codepoint |
MyEnum.Haxe |
T |
enum constructor with no arguments |
Furthermore, the internal syntax structure treats identifiers as constants, which may be relevant when working with macros.