Buffers and Files

 A file is named a list of characters stored on some form of secondary
 storage.

 A buffer is a structure in AE which has a name (usually a filename), and a
 language. A buffer holds a list of lines and is effectively equivelent to
 a fold. Some of these lines can be folds and virtual folds and so the buffer
 can hold a lot more than is visible at first sight.

 There are mechanisms for creating and deleting buffers, along with reading
 files into and out of them (ie: buffer_read and buffer_write).

 Because a buffer has a language associated with it, the editing
 characteristics of one buffer may differ from another.

 The language of a buffer is derived when the buffer is created from the
 filename the buffer is given. It does this by the use of a list of language
 definitions specified (usually) in the configuration file.

 Files can be read into a buffer using block_read and parts of a buffer
 may be written to a file using block_write.

 The editor stores folding information is reserved comments. These vary from
 language to language, and are set up by language_create. Because the
 folding information is stored in comments, any compilers and assemblers
 will ignore it. This eliminates the need for a 'folded file' to 'compilable
 file' conversion process.