This is the file that provides the core functionality of the Cerny.js library: interception, type checking, logging, dependency declaration, configuration and dictionaries.
To use the Cerny.js library this file must be included in your page. The configuration file (a copy of cerny.conf.js) must be included beforehand.
Some conventions used:
- If a current function or member is overwritten in a script, e.g. 'insertBefore', but will be referred to later, the new name of the member is composed of an underscore followed by the old name, e.g. '_insertBefore'.
- If a simple name is not possible due to keyword restrictions, the name is proceeded by an underscore, e.g. '_delete'.
- If a function takes arbitrarily many arguments, the documentation for these parameters must be called 'arguments'.
- If the documentation for a function does not specify a return value, the function returns undefined.
Constructor for a cloning exception.
Constructor for a contract violation.
A dictionary is a mapping from terms to definitions. Definitions may contain variables, which are terms with curly braces. A term can be looked up in a dictionary to get its definition by
. Any string can be evaluated by
A dictionary may contain a property
holding an array of strings denoting paths of dictionaries that will be included.
Create a logger. For every category there exists exactly one logger.
Check whether expr evaluates to true. If not throw a
. Only to be used in preconditions, postconditions and invariants.
Clone an object. Works for most cases with some restrictions:
- Custom types may provide a clone method. This method will be called with no parameters and the result will be returned.
- Cyclic references cannot be handeled: infinite recursion!
- Partial cloning is supported, if something is referenced in the object tree that cannot be cloned, an message is printed on the console and the referring property is undefined.
Dump a value for logging purposes. Returns the value of the variable followed by its type in braces. If the variable is a string, the value is enclosed by a single quote.
The empty function.
Evaluate a string. Replaces all variables in the string by its definitions in this dictionary.
Get a resource.
Returns the argument.
Instrument methods of an object for interception. Can be called multiple times with the same effect, only depending on
or the passed interceptors.
This function does not work on the
object in IE.
If one overrides methods of an existing object, where interception was already installed with this function and use this function again to intercept the method, the old method will be installed and a information will be logged. This is unfortunate, but is necessary so that interception always has the same effect. Workaround: Use
to attach the methods (best to both, but definitely when overriding) instead.
Check whether an expression is present during runtime.
false, if the string does not reference anything or the string references
Join functions into one function. The new function returns the return value of the last function.
Load a script. This function is called in
. It has different implementations in various environments (browser, Rhino [RHI]). The default runtime enviornment is the browser.
Load some data, can be an object, an array, a function or a primitive value.
Lookup a term in this dictionary.
Before 1.5: Return undefined if a term is not found. Staring with 1.5: Throw error if a term is not found.
undefinedif the term is unknown
Attach a function as a method to an object. This allows to create arbitrarliy many functions around the actual function. It aims for separation of concerns. The interceptors are wrapped around the function starting with the last one. This allows a "natural order", when filling the array regarding dependency. So more basic interceptors (e.g.
) are pushed first.
Create a namespace in
. This function is inspired by the Yahoo! UI Library [YUI].
Prototypal inheritance [DCP]. This alogorithm was developed by Douglas Crockford.
Specify the conditions that must be met in order to decide whether a function call was a success.
Postcondition is a function which is a sequence of calls to
has the same meaning as in the function called.
Postcondition is passed the following parameters:
- the return value,
- the old version of the object the call is made on, and then
- the arguments of the call.
Specify the conditions that must be met in order to decide whether a call to func can succeed. These conditions are collected in one function which is called the precondition. The precondition supports the author of a function in communicating the intent of the function to the consumer.
Precondition is a function which is a sequence of calls to
Precondition is passed the arguments of the call and
has the same meaning as in the function called.
Check for the presence of expressions. Loads an expression by looking it up in the catalog.
Resolve external dependencies declared in the catalog.
Specify the signature of a function. The types can be specified either by a string (
) or by a function, against which the actual value will be tested against with instanceof.
In the future it should be possible to specify an object as a type and the prototype chain is inspected for that object. Even more in the future it Cerny schemas could be used.