DOCSLIB.ORG

Ginger Documentation Release 1.0

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ginger Documentation Release 1.0 Ginger Documentation Release 1.0 sfkl / gjh Nov 03, 2017 Contents 1 Contents 3 2 Help Topics 27 3 Common Syntax 53 4 Design Rationales 55 5 The Ginger Toolchain 83 6 Low-Level Implementation 99 7 Release Notes 101 8 Indices and tables 115 Bibliography 117 i ii Ginger Documentation, Release 1.0 This documentation is still very much work in progress The aim of the Ginger Project is to create a modern programming language and its ecosystem of libraries, documen- tation and supporting tools. The Ginger language draws heavily on the multi-language Poplog environment. Contents 1 Ginger Documentation, Release 1.0 2 Contents CHAPTER 1 Contents 1.1 Overview of Ginger Author Stephen Leach Email [email protected] 1.1.1 Background Ginger is our next evolution of the Spice project. Ginger itself is a intended to be a rigorous but friendly programming language and supporting toolset. It includes a syntax-neutral programming language, a virtual machine implemented in C++ that is designed to support the family of Spice language efficiently, and a collection of supporting tools. Spice has many features that are challenging to support efficiently in existing virtual machines: pervasive multiple values, multiple-dispatch, multiple-inheritance, auto-loading and auto-conversion, dynamic virtual machines, implicit forcing and last but not least fully dynamic typing. The virtual machine is a re-engineering of a prototype interpreter that I wrote on holiday while I was experimenting with GCC’s support for FORTH-like threaded interpreters. But the toolset is designed so that writing alternative VM implementations is quite straightforward - and we hope to exploit that to enable embedding Ginger into lots of other systems. 1.1.2 Features of the Ginger Language and Tools Here’s a list of the features we have already implemented for the GVM project. • Pervasive multiple values, including loop expressions. • Dynamic type checking • Full arithmetic, supporting integers, big integers, rationals and doubles. • Immutable objects - strings, lists vectors and maps. • XML like elements built-in (immutable only). 3 Ginger Documentation, Release 1.0 • User-defined records and vectors. • First class functions and lambda expressions with full lexical binding. • Basic CGI integration. • Garbage Collection with weak references, weak maps and file closing. • Syntax Neutral with two available front-end syntaxes so far. • Multiple Implementations of Single Instruction Set 1.1.3 Further, Planned Features The Ginger project has an extensive roadmap that reflects our ambitions for it as a language. Here are some of the key features from the project roadmap that are not yet available. By and large most of these features are designed but require implementation. n.b. If there’s a particular feature of interest to you, let us know. • Regular expressions and supporting syntax. • Pattern Matching used pervasively to implement binding and smart loops. • Enhancements to the Garbage Collector • Dynamically Create New Virtual Machines as first class objects. • Implicit Force • Complex numbers. • Immutable, updateable, and dynamic strings, lists, vectors, elements and maps. • Optional static typing, consistent with the Dollin principle. • Full object-oriented programming model with multiple inheritance and multiple dispatch. • Coroutines as first class objects. • Keyword parameters with default values. • Partial application. • Auto-loading and auto-importing. • Updaters and deconstructors. • Advanced exception handling model with Alternative returns, Rollbacks, Failovers and Panics. • An additional Lisp-based front-end syntax. • Two further important built-in types: bags and priority queues • Full CGI Integration. • Full Unicode integration. 1.1.4 Development Status • Linux and Mac OS X, 64 & 32-bit versions of all 4 engines. • Common-syntax and C-style syntax front ends. • Basic function definitions & 1st class functions. • Conditions and short-circuit operators. 4 Chapter 1. Contents Ginger Documentation, Release 1.0 • Basic for loops. • Dynamic integer and double arithmetic & relational operators. • Primitive values (booleans, absent, Unicode characters). • Strings (8-bit only). • Lists, vectors, elements and maps (weak/hard, identity/equality). • Basic stream-based i/o working and integrated with garbage collector. • Garbage collector, includes weak refs and weak maps. • Basic packages working. • Full lexical binding, higher order functions. 1.2 About Ginger 1.2.1 What is Ginger Ginger is a modern programming system that is built on top of a general purpose virtual machine. It comes with a modern programming language and library so that you can use to write your own applications. But the whole system is designed to be open, so you can extend or replace almost every part of the system. Why did we create Ginger when there are so many programming systems already? Because we love programming and love making neat, effective programs. But other systems have all kind of conveniences that end up being confusing; strange corner cases that are supposed to be convenient but just make things ugly; or reasonable looking compromises that cause lots of problems later on. So we designed Ginger to be a language that gets out of your way and lets you enjoy the experience of writing a program. It took us a long time, more than ten years, to figure out what we thought that meant. Gradually we distilled our design goals into some key rules. One rule, for example, is “the programmer is in charge (not the language designer)”. That affects the design of visibility declarations such as private/public; it requires that a programmer can get access to private variables for, say, debugging or writing unit tests. You may wonder how this can make sense - in which case turn to the chapter on packages. Another key rule is “if one, why not many?”. This rule means that anywhere in the language where there is a restriction to one item, consider making it many items. So in Ginger expressions don’t return just one value, they may return any number from 0, 1, ... and so on. And methods don’t just dispatch on one special ‘this’ argument, they may dispatch on 0, 1, 2 ... of their arguments. In fact a function is just a special kind of method that dispatches on 0 arguments. To understand how we interpreted our design rules you need to know a little about Ginger. 1.2.2 Hello World in Common In this introduction to Ginger, we will write our examples in what we call ‘Common’. Ginger supports more than one programming language syntax. But we designed Common to be a neat modern language that is easy to remember and accident-resistant. But you don’t have to use it. We also designed a Javascript-inspired syntax too, if you prefer. And in future versions of Ginger we will add more - it’s quite easy to add new ones. (Why did we make Ginger so flexible? Because one of the things we wanted to get away from was the idea that there was a single right answer.) So what does Common look like? Here’s a simple ‘hello, world!’ example. It shows quite a few useful features. I have added line numbers for easy reference. 1.2. About Ginger 5 Ginger Documentation, Release 1.0 Line1 # Prints a cheery message to the console. Line2 define hello()=>> Line3 println("Hello, world!") Line4 enddefine On Line 1 we write an end-of-line comment which is introduced with a hash symbol followed by a space. On Line 2 we introduce a function called ‘hello’. Function definitions start with the keyword ‘define’ and are closed with the matching keyword ‘enddefine’. This pairing of opening and closing keywords is used in many places in Common. The function head is separated from the function body by an ‘=>>’. There are several places where this double-headed arrow is used in Common and it always signals that a function is being defined. On Line 3 we define the function body as calling the ‘println’ function on a literal string. The name ‘println’ is a contraction of ‘PRINT then add a LiNe’ and the function is part of the standard library (ginger.std) . Programmers do not usually import the standard library because it is available by default. String literals use double-quotes, just like C/C++/C#, Java, Javascript and so on. Single quotes are reserved for symbol literals, which you will meet later on, but for now you can think of as a different kind of string. On Line 4 we close the function with the ‘enddefine’ keyword. If you are working interactively you can abbreviate any keyword that starts with the prefix ‘end’ to just ‘end’. This includes ‘enddefine’, ‘endfn’, ‘endif’, ‘endfor’. 1.3 appginger, The Ginger XML Interpreter Usage : appginger [options] [files] OPTION SUMMARY -B, -batch run in batch mode -C, -cgi run as CGI script -I, -interactive run interactively -T, -terminate stop on mishap -d, -debug add debug option (see -help=debug) -h, -help print out this help info (see -help=help) -f, -projectfolder add a project folder to the search path -l, -license print out license information and exit -m<n> run using machine #n -v, -version print out version information and exit 1.4 Get Started with Ginger 1.4.1 Download, compile and install Ginger $ git clone [email protected]:Spicery/ginger.git $ cd ginger $ APPGINGER=`pwd` $ ./configure $ sudo make&& make install 6 Chapter 1. Contents Ginger Documentation, Release 1.0 1.4.2 Install RudeCGI library $ cd /tmp $ wget http://rudeserver.com/cgiparser/download/rudecgi-5.0.0.tar.gz $ tar zxf rudecgi-5.0.0.tar.gz $ pushd rudecgi-5.0.0; ./configure; sudo make&& make install; popd 1.4.3 Install optional extras $ sudo apt-get install
Load more

Recommended publications
  • GNU/Linux AI & Alife HOWTO
    GNU/Linux AI & Alife HOWTO GNU/Linux AI & Alife HOWTO Table of Contents GNU/Linux AI & Alife HOWTO......................................................................................................................1 by John Eikenberry..................................................................................................................................1 1. Introduction..........................................................................................................................................1 2. Symbolic Systems (GOFAI)................................................................................................................1 3. Connectionism.....................................................................................................................................1 4. Evolutionary Computing......................................................................................................................1 5. Alife & Complex Systems...................................................................................................................1 6. Agents & Robotics...............................................................................................................................1 7. Statistical & Machine Learning...........................................................................................................2 8. Missing & Dead...................................................................................................................................2 1. Introduction.........................................................................................................................................2
    [Show full text]
  • CST8207 – Linux O/S I
    Mounting a Filesystem Directory Structure Fstab Mount command CST8207 - Algonquin College 2 Chapter 12: page 467 - 496 CST8207 - Algonquin College 3 The mount utility connects filesystems to the Linux directory hierarchy. The mount point is a directory in the local filesystem where you can access mounted filesystem. This directory must exist before you can mount a filesystem. All filesystems visible on the system exist as a mounted filesystem someplace below the root (/) directory CST8207 - Algonquin College 4 can be mounted manually ◦ can be listed in /etc/fstab, but not necessary ◦ all mounting information supplied manually at command line by user or administrator can be mounted automatically on startup ◦ must be listed /etc/fstab, with all appropriate information and options required Every filesystem, drive, storage device is listed as a mounted filesystem associated to a directory someplace under the root (/) directory CST8207 - Algonquin College 5 CST8207 - Algonquin College 6 Benefits Scalable ◦ As new drives are added and new partitions are created, further filesystems can be mounted at various mount points as required. ◦ This means a Linux system does not need to worry about running out of disk space. Transparent ◦ No application would stop working if transferred to a different partition, because access to data is done via the mount point. ◦ Also transparent to user CST8207 - Algonquin College 7 All known filesystems volumes are typically listed in the /etc/fstab (static information about filesystem) file to help automate the mounting process If it is not listed in the /etc/fstab file, then all appropriate information about the filesystem needs to be listed manually at the command line.
    [Show full text]
  • Redacted for Privacy Professor Donald Guthrie, Jr
    AN ABSTRACT OF THE THESIS OF John Anthony Battilega for the DOCTOR OF PHILOSOPHY (Name) (Degree) in Mathematics presented on May 4, 1973 (Major) (Date) Title: COMPUTATIONAL IMPROVEMENTS TO BENDERS DECOMPOSITION FOR GENERALIZED FIXED CHARGE PROBLEMS Abstract approved Redacted for privacy Professor Donald Guthrie, Jr. A computationally efficient algorithm has been developed for determining exact or approximate solutions for large scale gener- alized fixed charge problems. This algorithm is based on a relaxa- tion of the Benders decomposition procedure, combined with a linear mixed integer programming (MIP) algorithm specifically designed to solve the problem associated with Benders decomposition and a com- putationally improved generalized upper bounding (GUB) algorithm which solves a convex separable programming problem by generalized linear programming. A dynamic partitioning technique is defined and used to improve computational efficiency.All component algor- ithms have been theoretically and computationally integrated with the relaxed Benders algorithm for maximum efficiency for the gener- alized fixed charge problem. The research was directed toward the approximate solution of a particular class of large scale generalized fixed charge problems, and extensive computational results for problemsof this type are given.As the size of the problem diminishes, therelaxations can be enforced, resulting in a classical Bendersdecomposition, but with special purpose sub-algorithmsand improved convergence pro- perties. Many of the results obtained apply to the sub-algorithmsinde- pendently of the context in which theywere developed. The proce- dure for solving the associated MIP is applicableto any linear 0/1 problem of Benders form, and the techniquesdeveloped for the linear program are applicable to any large scale generalized GUB implemen- tation.
    [Show full text]
  • X-Machines for Agent-Based Modeling FLAME Perspectives CHAPMAN & HALL/CRC COMPUTER and INFORMATION SCIENCE SERIES
    X-Machines for Agent-Based Modeling FLAME Perspectives CHAPMAN & HALL/CRC COMPUTER and INFORMATION SCIENCE SERIES Series Editor: Sartaj Sahni PUBLISHED TITLES ADVERSARIAL REASONING: COMPUTATIONAL APPROACHES TO READING THE OPPONENT’S MIND Alexander Kott and William M. McEneaney COMPUTER-AIDED GRAPHING AND SIMULATION TOOLS FOR AUTOCAD USERS P. A. Simionescu DELAUNAY MESH GENERATION Siu-Wing Cheng, Tamal Krishna Dey, and Jonathan Richard Shewchuk DISTRIBUTED SENSOR NETWORKS, SECOND EDITION S. Sitharama Iyengar and Richard R. Brooks DISTRIBUTED SYSTEMS: AN ALGORITHMIC APPROACH, SECOND EDITION Sukumar Ghosh ENERGY-AWARE MEMORY MANAGEMENT FOR EMBEDDED MULTIMEDIA SYSTEMS: A COMPUTER-AIDED DESIGN APPROACH Florin Balasa and Dhiraj K. Pradhan ENERGY EFFICIENT HARDWARE-SOFTWARE CO-SYNTHESIS USING RECONFIGURABLE HARDWARE Jingzhao Ou and Viktor K. Prasanna FROM ACTION SYSTEMS TO DISTRIBUTED SYSTEMS: THE REFINEMENT APPROACH Luigia Petre and Emil Sekerinski FUNDAMENTALS OF NATURAL COMPUTING: BASIC CONCEPTS, ALGORITHMS, AND APPLICATIONS Leandro Nunes de Castro HANDBOOK OF ALGORITHMS FOR WIRELESS NETWORKING AND MOBILE COMPUTING Azzedine Boukerche HANDBOOK OF APPROXIMATION ALGORITHMS AND METAHEURISTICS Teofilo F. Gonzalez HANDBOOK OF BIOINSPIRED ALGORITHMS AND APPLICATIONS Stephan Olariu and Albert Y. Zomaya HANDBOOK OF COMPUTATIONAL MOLECULAR BIOLOGY Srinivas Aluru HANDBOOK OF DATA STRUCTURES AND APPLICATIONS Dinesh P. Mehta and Sartaj Sahni PUBLISHED TITLES CONTINUED HANDBOOK OF DYNAMIC SYSTEM MODELING Paul A. Fishwick HANDBOOK OF ENERGY-AWARE AND GREEN COMPUTING Ishfaq Ahmad and Sanjay Ranka HANDBOOK OF GRAPH THEORY, COMBINATORIAL OPTIMIZATION, AND ALGORITHMS Krishnaiyan “KT” Thulasiraman, Subramanian Arumugam, Andreas Brandstädt, and Takao Nishizeki HANDBOOK OF PARALLEL COMPUTING: MODELS, ALGORITHMS AND APPLICATIONS Sanguthevar Rajasekaran and John Reif HANDBOOK OF REAL-TIME AND EMBEDDED SYSTEMS Insup Lee, Joseph Y-T.
    [Show full text]
  • File System, Files, and *Tab /Etc/Fstab
    File system, files, and *tab File system files directories volumes, file systems mounting points local versus networked file systems 1 /etc/fstab Specifies what is to be mounted where and how fs_spec: describes block special device for remote filesystem to be mounted fs_file: describes the mount point fs_vfstype: describes the type of file system fs_mntops: describes the mount options associated with the filesystem 2 /etc/fstab cont. fs_freq: used by the dump command fs_passno: used by fsck to determine the order in which checks are done at boot time. Root file systems should be specified as 1, others should be 2. Value 0 means that file system does not need to be checked 3 /etc/fstab 4 from blocks to mounting points metadata inodes directories superblocks 5 mounting file systems mounting e.g., mount -a unmounting manually or during shutdown umount 6 /etc/mtab see what is mounted 7 Network File System Access file system (FS) over a network looks like a local file system to user e.g. mount user FS rather than duplicating it (which would be a disaster) Developed by Sun Microsystems (mid 80s) history for NFS: NFS, NFSv2, NFSv3, NFSv4 RFC 3530 (from 2003) take a look to see what these RFCs are like!) 8 Network File System How does this actually work? server needs to export the system client needs to mount the system server: /etc/exports file client: /etc/fstab file 9 Network File System Security concerns UID GID What problems could arise? 10 Network File System example from our raid system (what is a RAID again?) Example of exports file from
    [Show full text]
  • Your Performance Task Summary Explanation
    Lab Report: 11.2.5 Manage Files Your Performance Your Score: 0 of 3 (0%) Pass Status: Not Passed Elapsed Time: 6 seconds Required Score: 100% Task Summary Actions you were required to perform: In Compress the D:\Graphics folderHide Details Set the Compressed attribute Apply the changes to all folders and files In Hide the D:\Finances folder In Set Read-only on filesHide Details Set read-only on 2017report.xlsx Set read-only on 2018report.xlsx Do not set read-only for the 2019report.xlsx file Explanation In this lab, your task is to complete the following: Compress the D:\Graphics folder and all of its contents. Hide the D:\Finances folder. Make the following files Read-only: D:\Finances\2017report.xlsx D:\Finances\2018report.xlsx Complete this lab as follows: 1. Compress a folder as follows: a. From the taskbar, open File Explorer. b. Maximize the window for easier viewing. c. In the left pane, expand This PC. d. Select Data (D:). e. Right-click Graphics and select Properties. f. On the General tab, select Advanced. g. Select Compress contents to save disk space. h. Click OK. i. Click OK. j. Make sure Apply changes to this folder, subfolders and files is selected. k. Click OK. 2. Hide a folder as follows: a. Right-click Finances and select Properties. b. Select Hidden. c. Click OK. 3. Set files to Read-only as follows: a. Double-click Finances to view its contents. b. Right-click 2017report.xlsx and select Properties. c. Select Read-only. d. Click OK. e.
    [Show full text]
  • Powerview Command Reference
    PowerView Command Reference TRACE32 Online Help TRACE32 Directory TRACE32 Index TRACE32 Documents ...................................................................................................................... PowerView User Interface ............................................................................................................ PowerView Command Reference .............................................................................................1 History ...................................................................................................................................... 12 ABORT ...................................................................................................................................... 13 ABORT Abort driver program 13 AREA ........................................................................................................................................ 14 AREA Message windows 14 AREA.CLEAR Clear area 15 AREA.CLOSE Close output file 15 AREA.Create Create or modify message area 16 AREA.Delete Delete message area 17 AREA.List Display a detailed list off all message areas 18 AREA.OPEN Open output file 20 AREA.PIPE Redirect area to stdout 21 AREA.RESet Reset areas 21 AREA.SAVE Save AREA window contents to file 21 AREA.Select Select area 22 AREA.STDERR Redirect area to stderr 23 AREA.STDOUT Redirect area to stdout 23 AREA.view Display message area in AREA window 24 AutoSTOre ..............................................................................................................................
    [Show full text]
  • Doing More in UNIX HORT 59000 Lab 3 Instructor: Kranthi Varala Today’S Pairs
    Doing more in UNIX HORT 59000 Lab 3 Instructor: Kranthi Varala Today’s pairs Pair #1 Pair #2 Pair #3 Pair #4 Pair #5 Pair #6 Pair #7 Pair #8 Aishwarya, Habte, Chancellor, Rachel F., Rachel H., Michelle, Raquel, Katherine, Shawna Xiaojin Thiti Sara AuditorX Jay Courtney Hannah If your partner is missing, let me know and we’ll adjust the pairs based on availability. Quiz 2 • Open-book policy: You are free to look at all the slides from previous Lectures and labs. • No internet searches for answers. • No talking to others. • You have 20 minutes to complete the quiz. Creating pipelines from commands • The STDIN and STDOUT of each command can be redirected to combine programs together. • For example, the STDOUT of one program can be sent to the STDIN of another program. • STDIN and STDOUT streams can be redirected using the following symbols: 1. > 2. < 3. | Writing vs. Appending to a file $ cat Pasture.txt > Poems.txt Send the contents of Pasture.txt to a new file called Poems.txt. If Poems.txt exists, its contents are over- written. $ cat WoodPile.txt >> Poems.txt Add the contents of WoodPile.txt to the end of the existing file Poems.txt. If Poems.txt does not exist, it will be created. Exercises UNIX commands wget and nano • Search NCBI’s GEO website for the experiment GSE49418. • Find the FTP link for the series matrix file. • Copy the link to the GSE49418_series_matrix.txt.gz file. • Use wget to download the matrix file to a new directory in your scratch folder.
    [Show full text]
  • The Evolution of Lisp
    1 The Evolution of Lisp Guy L. Steele Jr. Richard P. Gabriel Thinking Machines Corporation Lucid, Inc. 245 First Street 707 Laurel Street Cambridge, Massachusetts 02142 Menlo Park, California 94025 Phone: (617) 234-2860 Phone: (415) 329-8400 FAX: (617) 243-4444 FAX: (415) 329-8480 E-mail: [email protected] E-mail: [email protected] Abstract Lisp is the world’s greatest programming language—or so its proponents think. The structure of Lisp makes it easy to extend the language or even to implement entirely new dialects without starting from scratch. Overall, the evolution of Lisp has been guided more by institutional rivalry, one-upsmanship, and the glee born of technical cleverness that is characteristic of the “hacker culture” than by sober assessments of technical requirements. Nevertheless this process has eventually produced both an industrial- strength programming language, messy but powerful, and a technically pure dialect, small but powerful, that is suitable for use by programming-language theoreticians. We pick up where McCarthy’s paper in the first HOPL conference left off. We trace the development chronologically from the era of the PDP-6, through the heyday of Interlisp and MacLisp, past the ascension and decline of special purpose Lisp machines, to the present era of standardization activities. We then examine the technical evolution of a few representative language features, including both some notable successes and some notable failures, that illuminate design issues that distinguish Lisp from other programming languages. We also discuss the use of Lisp as a laboratory for designing other programming languages. We conclude with some reflections on the forces that have driven the evolution of Lisp.
    [Show full text]
  • UNIX X Command Tips and Tricks David B
    SESUG Paper 122-2019 UNIX X Command Tips and Tricks David B. Horvath, MS, CCP ABSTRACT SAS® provides the ability to execute operating system level commands from within your SAS code – generically known as the “X Command”. This session explores the various commands, the advantages and disadvantages of each, and their alternatives. The focus is on UNIX/Linux but much of the same applies to Windows as well. Under SAS EG, any issued commands execute on the SAS engine, not necessarily on the PC. X %sysexec Call system Systask command Filename pipe &SYSRC Waitfor Alternatives will also be addressed – how to handle when NOXCMD is the default for your installation, saving results, and error checking. INTRODUCTION In this paper I will be covering some of the basics of the functionality within SAS that allows you to execute operating system commands from within your program. There are multiple ways you can do so – external to data steps, within data steps, and within macros. All of these, along with error checking, will be covered. RELEVANT OPTIONS Execution of any of the SAS System command execution commands depends on one option's setting: XCMD Enables the X command in SAS. Which can only be set at startup: options xcmd; ____ 30 WARNING 30-12: SAS option XCMD is valid only at startup of the SAS System. The SAS option is ignored. Unfortunately, ff NOXCMD is set at startup time, you're out of luck. Sorry! You might want to have a conversation with your system administrators to determine why and if you can get it changed.
    [Show full text]
  • Filesystem Considerations for Embedded Devices ELC2015 03/25/15
    Filesystem considerations for embedded devices ELC2015 03/25/15 Tristan Lelong Senior embedded software engineer Filesystem considerations ABSTRACT The goal of this presentation is to answer a question asked by several customers: which filesystem should you use within your embedded design’s eMMC/SDCard? These storage devices use a standard block interface, compatible with traditional filesystems, but constraints are not those of desktop PC environments. EXT2/3/4, BTRFS, F2FS are the first of many solutions which come to mind, but how do they all compare? Typical queries include performance, longevity, tools availability, support, and power loss robustness. This presentation will not dive into implementation details but will instead summarize provided answers with the help of various figures and meaningful test results. 2 TABLE OF CONTENTS 1. Introduction 2. Block devices 3. Available filesystems 4. Performances 5. Tools 6. Reliability 7. Conclusion Filesystem considerations ABOUT THE AUTHOR • Tristan Lelong • Embedded software engineer @ Adeneo Embedded • French, living in the Pacific northwest • Embedded software, free software, and Linux kernel enthusiast. 4 Introduction Filesystem considerations Introduction INTRODUCTION More and more embedded designs rely on smart memory chips rather than bare NAND or NOR. This presentation will start by describing: • Some context to help understand the differences between NAND and MMC • Some typical requirements found in embedded devices designs • Potential filesystems to use on MMC devices 6 Filesystem considerations Introduction INTRODUCTION Focus will then move to block filesystems. How they are supported, what feature do they advertise. To help understand how they compare, we will present some benchmarks and comparisons regarding: • Tools • Reliability • Performances 7 Block devices Filesystem considerations Block devices MMC, EMMC, SD CARD Vocabulary: • MMC: MultiMediaCard is a memory card unveiled in 1997 by SanDisk and Siemens based on NAND flash memory.
    [Show full text]
  • Dynamic Functions in Dyalog
    Direct Functions in Dyalog APL John Scholes – Dyalog Ltd. [email protected] A Direct Function (dfn) is a new function definition style, which bridges the gap between named function expressions such as and APL’s traditional ‘header’ style definition. Simple Expressions The simplest form of dfn is: {expr} where expr is an APL expression containing s and s representing the left and right argument of the function respectively. For example: A dfn can be used in any function context ... ... and of course, assigned a name: Dfns are ambivalent. Their right (and if present, left) arguments are evaluated irrespective of whether these are subsequently referenced within the function body. Guards A guard is a boolean-single valued expression followed by . A simple expression can be preceded by a guard, and any number of guarded expressions can occur separated by s. Guards are evaluated in turn (left to right) until one of them yields a 1. Its corresponding expr is then evaluated as the result of the dfn. A guard is equivalent to an If-Then-Else or Switch-Case construct. A final simple expr can be thought of as a default case: The s can be replaced with newlines. For readability, extra null phrases can be included. The parity example above becomes: Named dfns can be reviewed using the system editor: or , and note how you can comment them in the normal way using . The following example interprets a dice throw: Local Definition The final piece of dfn syntax is the local definition. An expression whose principal function is a simple or vector assignment, introduces a name that is local to the dfn.
    [Show full text]