Hello, See image for my issue. Node works once, but not second time. In my case I’m trying to replace “TRUE” and “FALSE” string with boolean value. Dynamo 3.5.0 in Revit 2026 [image]

Yup. This has to do with Dynamo using truthy/falsy comparisons for text. [image] You can easily work around this by combining both conditions so you don’t end up with true/false values while the comparison is happening. [image]

Works the other way around? :thinking: This might be a weird edge case or something i have no idea about in dynamo :smiley: [image]

I reproduced this in 2024 [image] [image] I think what’s happening is that ReplaceByCondition sees the ‘true’ values and thinks that they are the result of the comparison does x = y. And then it goes yep and replaces the value, which is a bit dodgy.

Thanks Nick, that looks like a great solution, I will use that in future. All this logic talk made me think of the famous scene from labyrinth hehe. [labyrinth]

Replace by condition node unexpected output

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willyoungMF8K3 December 4, 2025, 2:40pm 4

It looks like this was covered in the below post:

Converting text to boolean - Lists-Logic - Dynamo

Topic		Replies	Views
Converting text to boolean Lists-Logic	11	7567	January 17, 2018
Converting true and false to custom text Revit dynamo	4	621	November 20, 2021
Replace by condition works unexpectedly with diffrent inputs Lists-Logic dynamo	4	396	August 20, 2018
Error with ReplaceByCondition in Dynamo Revit revit , dynamo	2	149	August 28, 2023
Replace by Condition ERROR Packages	3	1041	September 11, 2017

Replace by condition node unexpected output

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