Example
Below is an example of a simple Rake script to build a C Hello World program.
file'hello.o'=>'hello.c'dosh'cc -c -o hello.o hello.c'endfile'hello'=>'hello.o'dosh'cc -o hello hello.o'end
Rules
When a file is named as a prerequisite but it does not have a file task defined for it, Rake will attempt to synthesize a task by looking at a list of rules supplied in the Rakefile. For example, suppose we were trying to invoke task "mycode.o" with no tasks defined for it. If the Rakefile has a rule that looks like this:
rule'.o'=>'.c'do|t|sh"cc #{t.source} -c -o #{t.name}"endThis rule will synthesize any task that ends in ".o". It has as a prerequisite that a source file with an extension of ".c" must exist. If Rake is able to find a file named "mycode.c", it will automatically create a task that builds "mycode.o" from "mycode.c". If the file "mycode.c" does not exist, Rake will attempt to recursively synthesize a rule for it.
When a task is synthesized from a rule, the source attribute of the task is set to the matching source file. This allows users to write rules with actions that reference the source file.
Advanced rules
Any regular expression may be used as the rule pattern. Additionally, a proc may be used to calculate the name of the source file. This allows for complex patterns and sources.
The following rule is equivalent to the example above:
rule(/\.o$/=>->(t_name){t_name.sub/\.o$/,'.c'})do|t|sh"cc #{t.source} -c -o #{t.name}"endNOTE: Because of a quirk in Ruby syntax, parentheses are required around a rule when the first argument is a regular expression.
The following rule might be used for Java files:
rule'.class'=>->(t_name){t_name.sub(/\.class$/,'.java').sub(/^classes\//,'src/')}do|t|java_compile(t.source,t.name)endBelow is an example of a simple Rake recipe:
namespace:cakedodesc'make pancakes'task:pancake=>[:flour,:milk,:egg,:baking_powder]doputs"sizzle"endtask:butterdoputs"cut 3 tablespoons of butter into tiny squares"endtask:flour=>:butterdoputs"use hands to knead butter squares into 1 1/2 cup flour"endtask:milkdoputs"add 1 1/4 cup milk"endtask:eggdoputs"add 1 egg"endtask:baking_powderdoputs"add 3 1/2 teaspoons baking powder"endend
In computing, a namespace is a set of signs (names) that are used to identify and refer to objects of various kinds. A namespace ensures that all of a given set of objects have unique names so that they can be easily identified.
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A shell script is a computer program designed to be run by a Unix shell, a command-line interpreter. The various dialects of shell scripts are considered to be scripting languages. Typical operations performed by shell scripts include file manipulation, program execution, and printing text. A script which sets up the environment, runs the program, and does any necessary cleanup or logging, is called a wrapper.
Cake is a flour confection made from flour, sugar, and other ingredients and is usually baked. In their oldest forms, cakes were modifications of bread, but cakes now cover a wide range of preparations that can be simple or elaborate and which share features with desserts such as pastries, meringues, custards, and pies.
In software development, Make is a build automation tool that builds executable programs and libraries from source code by reading files called makefiles which specify how to derive the target program. Though integrated development environments and language-specific compiler features can also be used to manage a build process, Make remains widely used, especially in Unix and Unix-like operating systems.
In computer programming, glob patterns specify sets of filenames with wildcard characters. For example, the Unix Bash shell command mv *.txttextfiles/ moves all files with names ending in .txt from the current directory to the directory textfiles. Here, * is a wildcard and *.txt is a glob pattern. The wildcard * stands for "any string of any length including empty, but excluding the path separator characters ".
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Oxygene is a programming language developed by RemObjects Software for Microsoft's Common Language Infrastructure, the Java Platform and Cocoa. Oxygene is based on Delphi's Object Pascal, but also has influences from C#, Eiffel, Java, F# and other languages.
This comparison of programming languages compares the features of language syntax (format) for over 50 computer programming languages.
In computer programming, a comment is a programmer-readable explanation or annotation in the source code of a computer program. They are added with the purpose of making the source code easier for humans to understand, and are generally ignored by compilers and interpreters. The syntax of comments in various programming languages varies considerably.
In computer programming, scope is an enclosing context where values and expressions are associated. The scope resolution operator helps to identify and specify the context to which an identifier refers, particularly by specifying a namespace or class. The specific uses vary across different programming languages with the notions of scoping. In many languages, the scope resolution operator is written ::.
C# Open Source Managed Operating System (Cosmos) is a toolkit for building GUI and command-line based operating systems, written mostly in the programming language C# and small amounts of a high level assembly language named X#. Cosmos is a backronym, in that the acronym was chosen before the meaning. It is open-source software released under a BSD license.
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Jasmine is an open-source testing framework for JavaScript. It aims to run on any JavaScript-enabled platform, to not intrude on the application nor the IDE, and to have easy-to-read syntax. It is heavily influenced by other unit testing frameworks, such as ScrewUnit, JSSpec, JSpec, and RSpec.
In the C++ programming language, input/output library refers to a family of class templates and supporting functions in the C++ Standard Library that implement stream-based input/output capabilities. It is an object-oriented alternative to C's FILE-based streams from the C standard library.
Elixir is a functional, concurrent, high-level general-purpose programming language that runs on the BEAM virtual machine, which is also used to implement the Erlang programming language. Elixir builds on top of Erlang and shares the same abstractions for building distributed, fault-tolerant applications. Elixir also provides tooling and an extensible design. The latter is supported by compile-time metaprogramming with macros and polymorphism via protocols.
Objective-C is a high-level general-purpose, object-oriented programming language that adds Smalltalk-style messaging to the C programming language. Originally developed by Brad Cox and Tom Love in the early 1980s, it was selected by NeXT for its NeXTSTEP operating system. Due to Apple macOS’s direct lineage from NeXTSTEP, Objective-C was the standard programming language used, supported, and promoted by Apple for developing macOS and iOS applications until the introduction of the Swift programming language in 2014. Thereafter, its usage has been consistently declining among developers and it has often been described as a "dying" language.
Nim is a general-purpose, multi-paradigm, statically typed, compiled high-level systems programming language, designed and developed by a team around Andreas Rumpf. Nim is designed to be "efficient, expressive, and elegant", supporting metaprogramming, functional, message passing, procedural, and object-oriented programming styles by providing several features such as compile time code generation, algebraic data types, a foreign function interface (FFI) with C, C++, Objective-C, and JavaScript, and supporting compiling to those same languages as intermediate representations.
Bazel is a free and open-source software tool used for the automation of building and testing software. Google uses the build tool Blaze internally and released an open-sourced port of the Blaze tool as Bazel, named as an anagram of Blaze. Bazel was first released in March 2015 and was in beta status by September 2015. Version 1.0 was released in October 2019.
