Increases the content length by n elements.
Note that previously returned slices must not be used after this method has been invoked because the content buffer may be relocated, turning existing slices to it into dangling references.
number of characters to extend content by
slice to the portion in content by which content has been extended (last n elements in content after extension)
See Implementation
Increases the content length by n elements.
Note that previously returned slices must not be used after this method has been invoked because the content buffer may be relocated, turning existing slices to it into dangling references.