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Python

Posted by TJ Takei
TJ Takei
13,362 Points

'*' * length in place of for loop - where am I wrong?

I failed this Challenge Task as below: ... {% nam, dom = user.email.split('@',1) %} {% hid = nam[0] + ''(len(nam)-1) + '@' + dom %}' <div class="hidden name">{{ }}</div> ... I'm using '*'*length construct to hide the user name. The task asks to use a for-loop that I don't understand. Please help where I am wrong?

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 hide_email(user) %}
  {% nam, dom = user.email.split('@',1) %}
  {% hid = nam[0] + '*'*(len(nam)-1) + '@' + dom %}
  <div class="hidden email">{{ hid }}</div>
{% endmacro %}

2 Answers

Justin Foss
PLUS
Justin Foss
Courses Plus Student 8,808 Points
Justin Foss
Justin Foss
Courses Plus Student 8,808 Points

Also if you haven't checked it out, i would definitely take a look at the jinja documentation. I was stumped on this all afternoon, so I finally dove into the docs. They're really clean and easy to understand, and not only was I able to solve the problem, but after just a little reading I understand Jinja2 a lot more.

TJ Takei
TJ Takei
13,362 Points

Thanks! It works. Jinja2 looks like a python but not quite - lessons I learned.

stuartholland
stuartholland
10,773 Points
stuartholland
stuartholland
10,773 Points

Do look at some of the other answers to the macro question, Kenneth did a good job explaining.

  • you cannot use len() because Jinja2 barfs
  • for this string split, you need only the character on which you are splitting '@' and nothing more
  • rather than attempting to use * multiplied by len-1 (which, as I said, causes Jinja2 to barf), use a for loop like "for letter in nam[1:]" and have it print a * for each letter starting with slice at index 1
  • in order to declare nam and dom as variables you'll need a "with" declaration. This was just touched on in the "flash a message" unit of Flask Basics. Essentially, with enables you to call and set a variable for that instantiation only. It is one time and does not loop.

Like I said though, check out the one titled "Splitting the String" asked by Brandon Meredith it has this whole thing spelled out quite well. https://teamtreehouse.com/forum/splitting-the-string

TJ Takei
TJ Takei
13,362 Points

Thanks! It works. Brandon's article was also helpful.