add how to write a compiler

howto/how to write a compiler/readme.txt

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+TUTOR.ZIP
+
+This file contains all of the installments of Jack Crenshaw's
+tutorial on compiler construction, including the new Installment 15. 
+The intended audience is those folks who are not computer scientists,
+but who enjoy computing and have always wanted to know how compilers
+work. A lot of compiler theory has been left out, but the practical
+issues are covered. By the time you have completed the series, you
+should be able to design and build your own working compiler. It will
+not be the world's best, nor will it put out incredibly tight code.
+Your product will probably never put Borland or MicroSoft out of
+business.  But it will work, and it will be yours.
+
+A word about the file format: The files were originally created using
+Borland's DOS editor, Sprint.  Sprint could write to a text file only
+if you formatted the file to go to the selected printer.  I used the
+most common printer I could think of, the Epson MX-80, but even then
+the files ended up with printer control sequences at the beginning
+and end of each page.
+
+To bring the files up to date and get myself positioned to continue
+the series, I recently (1994) converted all the files to work with
+Microsoft Word for Windows.  Unlike Sprint, Word allows you to write
+the file as a DOS text file.  Unfortunately, this gave me a new
+problem, because when Word is writing to a text file, it doesn't
+write hard page breaks or page numbers.  In other words, in six years
+we've gone from a file with page breaks and page numbers, but
+embedded escape sequences, to files with no embedded escape sequences
+but no page breaks or page numbers.  Isn't progress wonderful?
+
+Of course, it's possible for me to insert the page numbers as
+straight text, rather than asking the editor to do it for me.  But
+since Word won't allow me to write page breaks to the file, we would
+end up with files with page numbers that may or may not fall at the
+ends of the pages, depending on your editor and your printer.  It
+seems to me that almost every file I've ever downloaded from
+CompuServe or BBS's that had such page numbering was incompatible
+with my printer, and gave me pages that were one line short or one
+line long, with the page numbers consequently walking up the page.  
+
+So perhaps this new format is, after all, the safest one for general
+distribution.  The files as they exist will look just fine if read
+into any text editor capable of reading DOS text files.  Since most
+editors these days include rather sophisticated word processing
+capabilities, you should be able to get your editor to paginate for
+you, prior to printing.
+
+I hope you like the tutorials.  Much thought went into them.
+
+
+									Jack W. Crenshaw
+
+								CompuServe 72325,1327
+