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Python

Posted by Victor Gavojdea
Victor Gavojdea
11,796 Points

Why do I need a for loop to print t***@example.com

I can't even begin to solve this because the for loop requirement is throwing ME for a loop (haha, seriously though, I don't even.)

lunch.py 
from flask import Flask, render_template

app = Flask(__name__)

@app.route('/')
def index():
    class User:
        email = None
    user = User()
    user.email = 'kenneth@teamtreehouse.com'
    return render_template('user.html', user=user)
templates/macro.html 
{% macro User %}
{% email = User.email.split('@') %}
{% for %}

{% endfor %}
{% endmacro %}

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

The idea behind using a loop is to print an asterisk for each character in the email name after the first character. You can peruse the other questions on this challenge to see how loops were used.

You pose an interesting question: can this challenge be solved without using a loop?

Yes! It can be by using length filter to get the number of asterisks needed.

  • {{ email[0][0] }}{# first char #}
  • {{ "*" * email[0][1:]|length }}{# replace remainder with '*' #}
  • @{# at-sign #}
  • {{ email[1] }}{# domain name #}

Putting them all together will yield the answer.

Also, the first line of the macro needs the macro name and parameter list:

  • {% macro hide_email(User) %}

Bonus: if you need to remove whitespace between printed elements, add a minus ("-") to either (or both) of the delimiters:

  • {{ --> {{- and }} --> -}}
  • {% --> {%- and %} --> -%}
Victor Gavojdea
Victor Gavojdea
11,796 Points

Incredibly helpful. Thank you!