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Venue MEDLEY LANGUAGE REFERENCE 1 Address comments to: Venue User Documentation 1549 Industrial Road San Carlos, CA 94070 415-508-9672 MEDLEY REFERENCE MANUAL VOLUME I: LANGUAGE April, 1993 Copyright 1985, 1991, 1993 by Venue. All rights reserved. Medley is a trademark of Venue. InterPress is a trademark of Xerox Corporation. PostScript is a registered trademark of Adobe Systems Inc. Copyright protection includes material generated from the software programs displayed on the screen, such as icons, screen display looks, and the like. The information in this document is subject to change without notice and should not be construed as a commitment by Venue. While every effort has been made to ensure the accuracy of this document, Venue assumes no responsibility for any errors that may appear. Text was written and produced with Venue text formatting tools; PostScript printers were used to produce masters. The typeface is Palatino. 2 TABLE of CONTENTS Volume 1 - Lanuage Reference 1. Introduction ......................................................................................................1 2. Litatoms (Symbols) ...................................................................................... 2-1 Using Symbols as Variables ......................................................................................2-1 Function Definition Cells...........................................................................................2-3 Property Lists ..............................................................................................................2-4 Print Names.................................................................................................................2-5 Characters and Character Codes..............................................................................2-9 3. Lists ................................................................................................................. 3-1 Creating Lists...............................................................................................................3-3 Building Lists from Left to Right..............................................................................3-4 Copying Lists ..............................................................................................................3-6 Extracting Tails of Lists..............................................................................................3-6 Counting List Cells.....................................................................................................3-8 Logical Operations .....................................................................................................3-9 Searching Lists ..........................................................................................................3-10 Substitution Functions .............................................................................................3-10 Association Lists and Property Lists......................................................................3-11 Sorting Lists...............................................................................................................3-13 Other List Functions.................................................................................................3-15 4. Strings ............................................................................................................ 4-1 5. Arrays ............................................................................................................. 5-1 6. Hash Arrays ................................................................................................... 6-1 Hash Overflow............................................................................................................6-3 User-Specified Hashing Functions...........................................................................6-3 7. Numbers and Arithmetic Functions ......................................................... 7-1 Generic Arithmetic .....................................................................................................7-2 Integer Arithmetic ......................................................................................................7-3 Logical Arithmetic Functions....................................................................................7-6 Floating-Point Arithmetic..........................................................................................7-8 Other Arithmetic Functions ....................................................................................7-10 8. Record Package ............................................................................................. 8-1 FETCH and REPLACE...............................................................................................8-1 1 CREATE....................................................................................................................... 8-2 TYPE? ........................................................................................................................... 8-3 WITH............................................................................................................................ 8-4 Record Declarations ................................................................................................... 8-4 Record Types....................................................................................................... 8-5 Optional Record Specifications ...................................................................... 8-10 Defining New Record Types .................................................................................. 8-12 Record Manipulation Functions............................................................................. 8-12 Changetran................................................................................................................ 8-13 Built-in and User Data Types ................................................................................. 8-15 9. Conditionals and Iterative Statements .................................................... 9-1 Data Type Predicates ................................................................................................. 9-1 Equality Predicates..................................................................................................... 9-2 Logical Predicates....................................................................................................... 9-3 COND Conditional Function.................................................................................... 9-3 The IF Statement......................................................................................................... 9-4 Selection Functions..................................................................................................... 9-5 PROG and Associated Control Functions .............................................................. 9-6 The Iterative Statement.............................................................................................. 9-7 I.s. Types .............................................................................................................. 9-8 Iterative Variable I.s.oprs .................................................................................. 9-9 Condition I.s.oprs............................................................................................. 9-12 Other I.s.oprs..................................................................................................... 9-13 Miscellaneous Hints on I.s.oprs ..................................................................... 9-13 Errors in Iterative Statements ......................................................................... 9-15 Defining New Iterative Statement Operators .............................................. 9-15 10. Function Definition, Manipulation, and Evaluation ........................ 10-1 Function Types ......................................................................................................... 10-2 Lambda-Spread Functions.............................................................................. 10-2 Nlambda-Spread Functions............................................................................ 10-3 Lambda-Nospread Functions......................................................................... 10-4 Nlambda-Nospread Functions....................................................................... 10-4 Compiled Functions......................................................................................... 10-5 Function Type Functions................................................................................. 10-5 Defining Functions................................................................................................... 10-7 Function Evaluation................................................................................................. 10-1 Iterating and Mapping Functions .......................................................................... 10-1 Function Arguments................................................................................................ 10-1 Macros........................................................................................................................ 10-1 DEFMACRO.................................................................................................... 10-15 Interpreting Macros ......................................................................................
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