from django import template
from django.template.defaultfilters import stringfilter

register = template.Library()

def truncateletters(value, arg):
    """
    Truncates a string after a certain number of letters
    
    Argument: Number of letters to truncate after
    """
    from django_extensions.utils.text import truncate_letters
    try:
        length = int(arg)
    except ValueError: # invalid literal for int()
        return value # Fail silently
    return truncate_letters(value, length)

truncateletters.is_safe = True
truncateletters = stringfilter(truncateletters)
register.filter(truncateletters)