How to iterate through a list of objects without repeating the same line of code

Question

Would you know how i can iterate through the self.checkxxx values so that I do not have to repeat the same if else clause over and over again. I am not sure how to do it if someone could give me an example that could be very useful Maybe like a for loop but the for loops i have tried have just not worked. I just get this error: TypeError: cannot unpack non-iterable CheckState object

def checkbox_ledVA(self):
        self.LED = 'PASS'
        self.LED_fail = 'FAIL'
        self.checkPWR_rot_va = self.ui.PWR_rot_VA.checkState()
        self.checkPWR_grun_va = self.ui.PWR_grun_VA.checkState()
        self.checkP1_va = self.ui.Port1_VA.checkState()
        self.checkP2_va = self.ui.port2_VA.checkState()
        self.checkP3_va = self.ui.Port3_VA.checkState()
     
        if self.checkPWR_rot_va == 2:
            self.checkPWR_rot_va = self.LED_pass
        else:
            self.checkPWR_rot_va = self.LED_fail
        
        if self.checkPWR_grun_va == 2:
            self.checkPWR_grun_va = self.LED_pass
        else:
            self.checkPWR_grun_va = self.LED_fail

        if self.checkP1_va == 2:
            self.checkP1_va = self.LED_pass
        else:
            self.checkP1_va = self.LED_fail
        
        if self.checkP2_va == 2:
            self.checkP2_va = self.LED_pass
        else:
            self.checkP2_va = self.LED_fail
        
        if self.checkP3_va == 2:
            self.checkP3_va = self.LED_pass
        else:
            self.checkP3_va = self.LED_fail

Please give me an example so i can learn and apply it to my program

Please update your question with the non-working code you have tried and the full error traceback. — quamrana
– quamrana, Commented Oct 19, 2022 at 12:21

Steven Rumbalski · Accepted Answer · 2022-10-19 12:58:01Z

2

Dispense with the entire if-else section and use a helper function when originally assigning attributes:

def checkbox_ledVA(self):
    self.LED = 'PASS'
    self.LED_fail = 'FAIL'

    pass_fail = lambda state: self.LED if state == 2 else self.LED_fail

    self.checkPWR_rot_va = pass_fail(self.ui.PWR_rot_VA.checkState())
    self.checkPWR_grun_va = pass_fail(self.ui.PWR_grun_VA.checkState())
    self.checkP1_va = pass_fail(self.ui.Port1_VA.checkState())
    self.checkP2_va = pass_fail(self.ui.port2_VA.checkState())
    self.checkP3_va = pass_fail(self.ui.Port3_VA.checkState())

edited Oct 19, 2022 at 12:58

answered Oct 19, 2022 at 12:37

Steven Rumbalski

45.7k10 gold badges96 silver badges125 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Byron · Accepted Answer · 2022-10-19 12:25:00Z

1

I would probably put the values in a dictionary or list and do something like

for i, val in enumerate(self.values):
    if val == 2:
        self.values[i] = self.LED_pass
    else:
        self.values[i] = self.LED_fail

answered Oct 19, 2022 at 12:25

Byron

3021 silver badge5 bronze badges

1 Comment

Ramas Over a year ago

ja, that was very useful but the returned values still came as 2 or 0 instead of pass or fail. but thank you it was nice

Josh Friedlander · Accepted Answer · 2022-10-19 12:29:17Z

1

Gratuitious one-liner:

[
    setattr(
        self,
        "checkP" + attrib + "_va",
        self.LED_pass
        if getattr(self, "checkP" + attrib + "_va") == 2
        else self.LED_fail,
    )
    for attrib in ["WR_rot", "WR_grun", "1", "2", "3"]
]

answered Oct 19, 2022 at 12:29

Josh Friedlander

11.8k7 gold badges42 silver badges89 bronze badges

2 Comments

Steven Rumbalski Over a year ago

It would be slightly less gratuitous as a two-liner with for attrib in ["WR_rot", "WR_grun", "1", "2", "3"]: on top rather than using a list-comprehension for side-effects only. Also it would display as one less line.

Josh Friedlander Over a year ago

true, although this code could be displayed as one line. but I would never use it in real life! stripping away the common prefixes and suffixes is a crime against readability

Collectives™ on Stack Overflow

How to iterate through a list of objects without repeating the same line of code

3 Answers 3

Comments

1 Comment

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

1 Comment

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related