Coverage for nltk.yamltags : 58%

""" 

Register YAML tags in the NLTK namespace with the YAML loader, by telling it 

what module and class to look for. 

NLTK uses simple '!' tags to mark the types of objects, but the fully-qualified 

"tag:nltk.org,2011:" prefix is also accepted in case anyone ends up 

using it. 

""" 

import yaml 

def custom_import(name): 

    components = name.split('.') 

    module_path = '.'.join(components[:-1]) 

    mod = __import__(module_path) 

    for comp in components[1:]: 

        mod = getattr(mod, comp) 

    return mod 

def metaloader(classpath): 

    def loader(*args, **kwds): 

        classref = custom_import(classpath) 

        return classref.from_yaml(*args, **kwds) 

    return loader 

def register_tag(tag, classpath): 

    yaml.add_constructor('!'+tag, metaloader(classpath)) 

    yaml.add_constructor('tag:nltk.org,2011:'+tag, 

                         metaloader(classpath)) 

register_tag('tag.Unigram', 'nltk.tag.unigram.Unigram') 

register_tag('tag.Brill', 'nltk.tag.brill.Brill') 

__all__ = ['custom_import', 'metaloader', 'register_tag']