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== Cocktails - How To Make A Rum Fix Cocktail ==
  
== Programming Topics ==
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[[Image:Example123213213689.jpg]]
  
=== ConTeXt Features ===
+
There are different ways in making '''[http://www.mymixeddrinks.com cocktails]''', it's up on you what kind of '''cocktail''' you would like to make. This article will tell you non how to make a Rum Fix cocktail. Just like any other cocktail a Run Fix cocktail has an ingredients needed to complete it, there is also a step to be followed to get the best taste of it. You will enjoy this recipe for a Rum Fix cocktail. A thirst quenching rum based drink with a splash of lemon taste. Lemon is one of the important ingredients in making  a cocktail it adds some looks to your '''cocktail''' and also adds flavor on it.
* [[Modes]]: Conditional processing of text
 
  
=== Commands and Arguments ===
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[[Image:Example12321321555.jpg]]
* [[System Macros]] (temporary variables, expansion control, argument grabbing and handling, definitions and assignments, branches and decisions, cases, comma separated lists, assignments and paramters, user intraction)
 
* [[Programming in LuaTeX]]
 
* [[Commands with KeyVal arguments|Commands with Key=Value arguments]]: For things like <code>\command[thiskey=thatvalue]</code>.  
 
* [[Commands with optional arguments]]: One or more optional arguments within brackets.
 
  
=== Module Parameters ===
+
In making it a rum fix '''[http://www.mymixeddrinks.com cocktails]''' of course first thing to do is to prepare the ingredients like caster sugar, water, lemon juice, dark opr light rum, maraschino cherry, a lemon slice and one of the most important ingredients the ice cubes. Be sure to complete your ingredients before making it to make a good taste in your '''cocktail'''. Now, first step to do is measure and add the sugar, water and lemon juice in the glass. Then, stir contents well with a stirrer or spoon. Add ice cubes to the glass, Measure and add the rum and stir ingredients together again and garnish your '''drink''' with a wedge of lemon and the cherry.
* [[Module Parameters]]: Passing parameters to modules.
 
 
 
=== Programming Techniques ===
 
* [[Processing Lists]]: Processing lists of values
 
* [[Counters]]: Manipulating counters in context
 
* [[Expressions]]: Evaluating expressions of type number, dimen, glue or muglue
 
* [[executesystemcommand]]: process contents of an environment by another program
 
* Loops and expansion [http://randomdeterminism.wordpress.com/2009/03/05/tex-programming-the-past-the-present-and-the-future/ (blog post)]
 
 
 
=== Debugging ===
 
 
 
* [[Console Mode]]: Using ConTeXt on keyboard input directly, rather than loading a <tt>.tex</tt> file.
 
 
 
== Using variables ==
 
 
 
There are several ways to handle variables in ConTeXt.
 
The recommended and easiest method is to use the
 
<tt>\setvariables</tt> and <tt>\getvariable</tt> macros.
 
Doing it this way you also avoid to get in conflict with
 
already defined stuff (as variables use their own namespace).
 
 
 
To store variables, you can use the <tt>\setvariables</tt>
 
macro.
 
 
 
<texcode>
 
% stores value in variable namespace:key
 
\setvariables[namespace][key=value]
 
% stores the expanded value
 
\setevariables[namespace][key=value]
 
% global
 
\setgvariables[namespace][key=value]
 
% global and expanded value
 
\setxvariables[namespace][key=value]
 
</texcode>
 
 
 
Use <tt>\getvariable</tt> to process a variable. Reading an undefined
 
variable results in the <tt>\empty</tt> token. This is not a serious problem,
 
as long as you expect text only.
 
But be warned: the compilation process breaks, if you expect a dimension
 
or number. So better take care, that you define your variables, before you use them.
 
 
 
<texcode>
 
% gets value of the variable namespace:key
 
\getvariable{namespace}{key}
 
</texcode>
 
 
 
 
 
To avoid problems, also pay attention to the following:
 
 
 
You can set several variables (same namespace) at the same time.
 
So the command <tt>\setvariables</tt> logically uses the '''plural''' form
 
and works with '''square brackets'''.
 
On the other hand you can only process one variable at the same time, so
 
<tt>\getvariable</tt> uses the '''singular''' form and works with '''braces'''.
 
 
 
 
 
 
 
OK, here comes a simple example. Let's say, that we want to have variable
 
space before and after a letter macro called <tt>\Opening</tt>.
 
 
 
<texcode>
 
\long\def\Opening#1{%
 
  \getvariable{Letter:opening}{before}
 
  \noindent{\begstrut#1\endstrut}
 
  \getvariable{Letter:opening}{after}
 
}
 
</texcode>
 
 
 
By using variables in your macros, you can separate the layout definition,
 
so that your macros get much more flexible.
 
Just ensure, that all variables are set, before you use them!
 
 
 
In this example we want to have a blank line in front of the opening, and
 
two blank lines right after it. The value for the second key contains
 
square brackets, so it must be enclosed in braces.
 
 
 
<texcode>
 
\setvariables[Letter:opening]
 
  [before=\blank,
 
  after={\blank[2*big]},
 
  ]
 
</texcode>
 
 
 
You can now save this style setup (among others) in a separate file and
 
include it at the start of your document (before <tt>\Opening</tt> is
 
defined or at least used).
 
 
 
And don't forget:
 
'''Just ensure, that all variables are set, before you use them!'''
 
 
 
 
 
==== Using setups for namespaces ====
 
Using <tt>\setups</tt> for a variable namespace allows an easier control over the
 
containing variables.
 
All you have to do is to define the setups
 
<tt>namespace:set</tt> and/or <tt>namespace:reset</tt>
 
for a given namespace.
 
Now every time a variable of that namespace is assigned (written), ConTeXt
 
automatically calls these setups. Reading of variables is totally unaffected by these
 
settings.
 
A possible use are default values, calculations and even verification.
 
 
 
So once you have 'setup' your variables proper, you don't have to worry about
 
unset variables and alike any more. Also changes can be made easy, as there is only
 
one common setup.
 
The drawback is the slower speed in use,
 
as every assignment to a variable calls these setups.
 
 
 
 
 
To give you the idea, try this example.
 
 
 
The <tt>set</tt>-part is called
 
* '''right after''' the definition of the namespace (initialisation) and
 
* '''after''' a value is assigned to a variable.
 
The <tt>reset</tt>-part is called
 
* '''right after''' any assignment, but still in front of the <tt>set</tt>-part.
 
 
 
<texcode>
 
\setupoutput[pdftex]
 
 
 
\startsetups namespace:set
 
%
 
\writestatus{VARIABLES}{namespace:set is beeing called..}%
 
\ {\green [namespace:set]}
 
  % whatever must be done with your variables after you assign a value
 
  %
 
  % (initialisation with defaults,..)
 
\stopsetups
 
 
 
 
 
\startsetups namespace:reset
 
%
 
\writestatus{VARIABLES}{namespace:set is beeing called..}%
 
\ {\green [namespace:reset]}
 
  % whatever must be done after an assignment (verification, calculation,..)
 
\stopsetups
 
 
 
 
 
% \setups[namespace:set] is automatically called right after 'set' is assigned
 
\setvariables[namespace]
 
  [set={\setups[namespace:set]},
 
  reset={\setups[namespace:reset]},
 
  ]
 
 
 
% watch for the colors
 
\setupcolors[state=start]
 
 
 
\starttext
 
\hairline
 
{\bf reading has no effect\par}
 
{\tt Calling \type{\getvariable{namespace}{key}}...\getvariable{namespace}{key}}
 
 
 
\blank
 
{\bf writing calls reset and set\par}
 
{\tt Calling \type{\setvariables[namespace][key=value]}...\setvariables[namespace][key=value]}
 
 
 
\stoptext
 
 
 
</texcode>
 
 
 
== Defining new commands ==
 
 
 
=== Special characters in command names ===
 
 
 
Some commands have special characters in their names, that TeX normally does not consider to be
 
letters: <tt>@</tt>, <tt>!</tt> and <tt>?</tt>.
 
Before and after the use or definition of such protected commands in your input files, the catcode of these
 
characters has to be changed. This is done by <cmd>unprotect</cmd> and <cmd>protect</cmd>:
 
 
 
<texcode>
 
\unprotect
 
\def\!test{alfa}
 
\protect
 
</texcode>
 
 
 
The newly defined command <tt>\!test</tt> can of course only be called upon when we are in the <cmd>unprotect</cmd>ed state, otherwise TeX reads the command <tt>\!</tt>, followed by the word <tt>test</tt> (and probably complains loudly about not being in math mode). These protection/unprotection commands can be nested.  When the nesting becomes deeper than one level, the system reports the current protection level. It is a good habit to always start your macro files with <cmd>unprotect</cmd> and end them with <cmd>protect</cmd>.
 
 
 
 
 
 
 
== Passing verbatim text as macro parameter ==
 
 
 
(For passing text to LuaTex verbatim, see the [[Programming_in_LuaTeX#Manipulating_verbatim_text_for_dummies|Programming in LuaTeX]] article on this wiki.)
 
 
 
In case you want to write macros that should handle verbatim text,
 
you can use the tex primitives <tt>\obeyspaces</tt> and <tt>\obeylines</tt>.
 
<tt>\obeyspaces</tt> changes the category code of the space character,
 
so that spaces become significant. <tt>\obeylines</tt> does the same for the
 
newline character.
 
 
 
This works fine for the following example:
 
 
 
<texcode>
 
\framed{\obeyspaces{A gap from here    to there!}}
 
</texcode>
 
 
 
<context>
 
\framed{\obeyspaces{A gap from here    to there!}}
 
</context>
 
 
 
But if you pass this text as a parameter for your own macro
 
<tt>\TextWithSpaces</tt>
 
 
 
<texcode>
 
\def\TextWithSpaces#1{\framed{\obeyspaces#1}}%
 
\TextWithSpaces{A gap from here    to there!}
 
</texcode>
 
 
 
<context>
 
\def\TextWithSpaces#1{\framed{\obeyspaces#1}}%
 
\TextWithSpaces{A gap from here    to there!}
 
</context>
 
 
 
the additional spaces are '''ignored'''.
 
This happens because the category code change is not yet in effect when
 
the argument is parsed, and the spaces are removed during parsing.  To keep
 
the spaces, the catcode change must be done '''before''' the argument is parsed.
 
 
 
Here is a two-part solution for the problem (''suggested by Taco Hoekwater''):
 
 
 
<texcode>
 
\def\TextWithSpaces{\bgroup\obeyspaces\doTextWithSpaces}
 
\def\doTextWithSpaces#1{\framed{#1}\egroup}
 
</texcode>
 
 
 
Another way is to postpone argument loading (''suggested by Hans Hagen'').
 
 
 
<texcode>
 
\def  \TextWithSpaces  {\framed\bgroup\obeyspaces\doTextWithSpaces}
 
\def\doTextWithSpaces    #1{#1\egroup}
 
</texcode>
 
 
 
Both of these produce the desired result:
 
 
 
<context>
 
\def  \TextWithSpaces  {\framed\bgroup\obeyspaces\doTextWithSpaces}
 
\def\doTextWithSpaces    #1{#1\egroup}
 
 
 
\TextWithSpaces{A gap from here    to there!}
 
</context>
 
 
 
== Setups ==
 
In ConTeXt it is easy to create local variables and grouping. Local variables can be simulated as in:
 
 
 
<texcode>
 
\startsetups whatever
 
% some useful definitions here
 
\stopsetups
 
 
 
\definestartstop[whatever][commands=\setups{whatever}]
 
 
 
\startwhatever
 
Using definitions here.
 
\stopwhatever
 
</texcode>
 
 
 
But you can place setups almost everywhere and environment will not be affected by their execution. It is useful to wrap overlay definitions and such in setups as in (copied from [[Colorful_CD_Inlay]] page):
 
 
 
<texcode>
 
\defineoverlay [origin] [\setups{origin}]
 
 
 
\startsetups origin
 
    \vbox to \overlayheight {
 
        \vfill\tfxx\setstrut
 
        \hsize\overlaywidth
 
        \hfill Fiona Apple\enspace EM\enspace2005\quad\strut\endgraf
 
        \kern1ex
 
    }
 
\stopsetups
 
</texcode>
 
 
 
You can even do things like:
 
 
 
<texcode>
 
\starttext
 
\startsetups settest
 
\def\command{do something with}
 
I want to \command{} command.
 
\stopsetups
 
 
 
\start
 
\setups{settest}
 
\stop
 
 
 
\command aaa  % will give "undefined control sequence" error
 
 
 
\stoptext
 
</texcode>
 
 
 
[[Category:Inside ConTeXt]]
 

Revision as of 17:16, 19 January 2011

Cocktails - How To Make A Rum Fix Cocktail

File:Example123213213689.jpg

There are different ways in making cocktails, it's up on you what kind of cocktail you would like to make. This article will tell you non how to make a Rum Fix cocktail. Just like any other cocktail a Run Fix cocktail has an ingredients needed to complete it, there is also a step to be followed to get the best taste of it. You will enjoy this recipe for a Rum Fix cocktail. A thirst quenching rum based drink with a splash of lemon taste. Lemon is one of the important ingredients in making a cocktail it adds some looks to your cocktail and also adds flavor on it.

File:Example12321321555.jpg

In making it a rum fix cocktails of course first thing to do is to prepare the ingredients like caster sugar, water, lemon juice, dark opr light rum, maraschino cherry, a lemon slice and one of the most important ingredients the ice cubes. Be sure to complete your ingredients before making it to make a good taste in your cocktail. Now, first step to do is measure and add the sugar, water and lemon juice in the glass. Then, stir contents well with a stirrer or spoon. Add ice cubes to the glass, Measure and add the rum and stir ingredients together again and garnish your drink with a wedge of lemon and the cherry.