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Problem using 'len' function to print correct number of asterisks.

I'm trying to use this line:

{{ user.email[0] + '*'*(len(user.email.split('@')[0])-1) + '@' + user.email.split('@')[-1] }}

as seen in templates/macro.html. It seems like everything works except for printing out the asterisks. I'm at a loss what to do..

from flask import Flask, render_template

app = Flask(__name__)

def index():
    class User:
        email = None
    user = User()
    user.email = 'kenneth@teamtreehouse.com'
    return render_template('user.html', user=user)
{% macro hide_email(user) %}
  {{ user.email[0] + '*'*(len(user.email.split('@')[0])-1) + '@' + user.email.split('@')[-1] }}
{% endmacro %}

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

A very interesting approach! The issue is the Python len() function isn't available in the templates. However there is a filter available that will give you what you want. Modifying your macro:

{% macro hide_email(user) %}
  {{ user.email[0] + '*'* ((user.email.split('@')[0] | length)-1) + '@' + user.email.split('@')[-1] }}
{% endmacro %}

This solution worked, thank you!