uPython syntax errors

[Netrosec]

I use uPyCraft on a esp8266 board. I am working with an mqtt example for uPython i adapted to publish a simple message when light levels drops below a given threshold but i get this error:

exec(open(‘main.py’).read(),globals())
Traceback (most recent call last):
File “<stdin>”, line 1, in <module>
File “<string>”, line 43
SyntaxError: invalid syntax

Below is my main code.

Code: Select all

from machine import Pin, ADC
from time import sleep

ldr = ADC(0)


def sub_cb(topic, msg):
  print((topic, msg))
if topic == b'notification' and msg == b'received':
  print('ESP received hello message')


def connect_and_subscribe():
  global client_id, mqtt_server, topic_sub
  client = MQTTClient(client_id, mqtt_server)
  client.set_callback(sub_cb)
  client.connect()
  client.subscribe(topic_sub)
  print('Connected to %s MQTT broker, subscribed to %s topic' % (mqtt_server, topic_sub))
  return client
  
  
def restart_and_reconnect():
  print('Failed to connect to MQTT broker. Reconnecting...')
  time.sleep(10)
  machine.reset()
  
  
try:
  client = connect_and_subscribe()
except OSError as e:
  restart_and_reconnect()
  
  
while True:
  ldrValue = ldr.read()
  print(ldrValue)
  sleep(0.1)
  
if ldrValue >= 350
  msg = b'laser0 #%d' % counter
  client.publish(topic_pub, msg)
  last_message = time.time()
  counter += 1
except OSError as e:
  restart_and_reconnect()

[Roberthh]

Please check what you posted. There is an except clause at the end without an matching try, and the indentation also seems wrong.

[Netrosec]

Please check what you posted. There is an except clause at the end without an matching try, and the indentation also seems wrong.

OK, so i checked and pasted your edited code and the error stopped. But ldr does not give me a reading..

[Netrosec]

Please check what you posted. There is an except clause at the end without an matching try, and the indentation also seems wrong.

OK, so i checked and pasted your edited code and the error stopped. But ldr does not give me a reading..

Ooops. the error still persists.

[Roberthh]

Please re-post your code.
Edit: it is usually better not to put your code in "main.py", but in a file with a different name which you then can import from REPL or main.py

[Netrosec]

Advice well taken. But the problem isn't yet resolved.

[Roberthh]

I still have the problem that what you posted is not well formatted python code, but that should give different error messages. Therefore i asked to re-post the code. The posting may have corrupted it.

[Netrosec]

I understand that uPython uses 2 spaces indentation as opposed to regular python which uses 4 spaces indentation. I have fixed the formatting problem.

[Roberthh]

UPython works like cPython with respect to indentation. You can use any number of spaces, as long as it is consistent in a level per block.

[pythoncoder]

It is also vital (in Python or MicroPython code) not to mix tabs and spaces. That leads to code which looks fine but won't work. Ensure your editor converts tabs to spaces.