Class ExtensionRegistry

source code

Associate a file loader with an extension.

Note that there may be multiple loaders for the same extension.

Example
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registry = ExtensionRegistry()

# Add an association by setting an element
registry['.zip'] = unzip

# Multiple extensions for one loader
registry['.tgz'] = untar
registry['.tar.gz'] = untar

# Generic extensions to use after trying more specific extensions;
# these will be checked after the more specific extensions fail.
registry['.gz'] = gunzip

# Multiple loaders for one extension
registry['.cx'] = cx1
registry['.cx'] = cx2
registry['.cx'] = cx3

# Show registered extensions
print registry.extensions()

# Can also register a format name for explicit control from caller
registry['cx3'] = cx3
print registry.formats()

# Retrieve loaders for a file name
registry.lookup('hello.cx') -> [cx3,cx2,cx1]

# Run loader on a filename
registry.load('hello.cx') ->
    try:
        return cx3('hello.cx')
    except:
        try:
            return cx2('hello.cx')
        except:
            return cx1('hello.cx')

# Load in a specific format ignoring extension
registry.load('hello.cx',format='cx3') ->
    return cx3('hello.cx')