True/False Designscript weirdness

DesignScript
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Why isn’t this outputting false?
true blatantly does not equal “Cancel”. :frowning:

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Try just testing A[0] == "Cancel"; and see what you get.

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I get true. :frowning:

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@Alien ,

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i think A is occupied by something…

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KR

Andreas

5

meh… back to Python then :rofl:

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Hi @Alien I guess it will work if you take string from object…seems it cant compare a system bool with a string…but not sure

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So the reason I asked this, is that I hoped it would trigger the indication that the root cause is lacing/replication guides, in particular that you can’t utilize them inside an if statement.

So what you need to do is ask “is the first item in A equal to the target?”
Then on the next line say “if that was true get me the true value; otherwise get me the false value.”

By running it as two actions you circumvent the limitation of the if statement.

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It apparently is :roll_eyes:
TrueFalse-1

But isn’t if you consider them to be two objects
TrueFalse-2

So to solve your problem …

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And miss the potentially awesome Design Script journey that lies ahead? :stuck_out_tongue_winking_eye:

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Python > Designscript

:nerd_face:

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This is because the “equal to” condition is truthy/falsy.

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11

Sort of… Design Script (and therefore Dynamo) will attempt to convert to common types when doing comparison.
ie: 1.0 == 1;

This extends to booleans, where anything other than 0, “”, NaN, null, or other “empty” data types will convert to a value of true, as the object exists.

So:

    Point.Origin() == True; //true
    "Turnip" == true; //true
    1 == true; //true
    Point.ByCoordinates("cat",0,0) == true; //false (maybe a warning instead)
    "" == true; //false
    0 == true; //false
    //
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It shows perfectly to not take things for granted. Computers do exactly what you tell them to do, not what you expect them to do…

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This was my understanding of truthy/falsy. Is the only difference here that Design Script first attempts a conversion? So basically, Design Script does some cleanup/simplifying in order to compare like objects but then reverts to truthy/falsy when object types aren’t comparable?

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if the objects are not the same type, it will attempt to convert them to the same type; Booleans are the most complex of the types. The design script language manual has a full chart (no link handy and I’m on my phone - sorry).

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For anybody else who’s interested.

3.4. Type conversion rules
DesignScriptGuide_.pdf (460.1 KB)

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