2299	 An Extensible Editor for a Small Machine with Disk Storage	 A design philosophy for developing a sophisticated utility program is illustrated by the actual design and implementation of a text editor. A versatile data structure is employed so that only a small number of programmed subroutines are necessary for all types of data manipulation. Such a data structure is described and its merits are illustrated by the ease with which powerful extensions can be implemented in terms of a few basic editing function. command processing context searching executive program garbage collection interpreter list processing macro language paging parameter substitution recursion state table storage allocation string manipulation text editing virtual memory
