NameError: name ‘true’ is not defined [closed]

Closed. This question is not reproducible or was caused by typos. It is not currently accepting answers.

This question was caused by a typo or a problem that can no longer be reproduced. While similar questions may be on-topic here, this one was resolved in a way less likely to help future readers.

Closed 7 years ago.

The community reviewed whether to reopen this question 2 months ago and left it closed:

Original close reason(s) were not resolved

Improve this question

I want to use Boolean ( true / false ) in my python source file, but after running the application, I receive the following error:

NameError: name 'true' is not defined

JavaScript
​x
 
NameError: name 'true' is not defined
​

The error lies on while true:, when I am trying to make the Raspberry Pi run a HTML script when it receives input on port 17:

import RPi.GPIO as GPIO
import time
import os

inputSignal = 17
GPIO.setmode(GPIO.BCM)
GPIO.setup(inputSignal,GPIO.IN)

while true:
    if (GPIO.input(inputSignal)):
        os.system("html /home/pi/index.html")
    else:
        print("No Input")

JavaScript
 
import RPi.GPIO as GPIO
import time
import os
​
inputSignal = 17
GPIO.setmode(GPIO.BCM)
GPIO.setup(inputSignal,GPIO.IN)
​
while true:
    if (GPIO.input(inputSignal)):
        os.system("html /home/pi/index.html")
    else:
        print("No Input")
​

Answer

Python’s boolean constants are capitalized: True and False with upper case T and F respectively.

The lower-case variants are just valid free names for variables, so you could use them for whatever you want, e.g. true = False (not recommended ;P).

Advertisement

Answer