FlexField - Validators - how Boolean are managed in the Groovy expression

Summary

I would like to use a boolean flexfield in a groovy expression

Content

Hello,

Imagine 2 flexfields :

• "Flag" is TRUE_FALSE
• "Type" has a value set (having 4 values possible : H, B, N or L, each value having a specific functional signification)

I want to create a Validator in order to raise an error with the following rule:

• If the Type is H or B or L and Flag is false, prompt the error 'Error Message'.

I thought it easy and so the expression is :

(FlexSeg?.Type == 'H' || FlexSeg?.Type == 'B' || FlexSeg?.Type == 'L') && FlexSeg?.Flag == false

It is a valid expression but it prompt the error all the time.