A String buffer is an efficient way to build a big string by appending small elements together.
Its cross-platform implementation uses String concatenation internally, but StringBuf may be optimized for different targets.
Unlike String, an instance of StringBuf is not immutable in the sense that it can be passed as argument to functions which modify it by appending more values. However, the internal buffer cannot be modified.
Appends the representation of x to this StringBuf.
The exact representation of x may vary per platform. To get more
consistent behavior, this function should be called with
Std.string(x).
If x is null, the String "null" is appended.
Appends the character identified by c to this StringBuf.
If c is negative or has another invalid value, the result is
unspecified.
inline addSub (s:String, pos:Int, ?len:Int):Void
Appends a substring of s to this StringBuf.
This function expects pos and len to describe a valid substring of
s, or else the result is unspecified. To get more robust behavior,
this.add(s.substr(pos,len)) can be used instead.
If s or pos are null, the result is unspecified.
If len is omitted or null, the substring ranges from pos to the end
of s.