---
title: "More Truth in Programming"
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url: "http://localhost/article/more-truth-in-programming/"
markdown_url: "http://localhost/article/more-truth-in-programming.md"
published_at: "2020-10-27T17:18:35+00:00"
modified_at: "2024-06-23T00:43:54+00:00"
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  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "As long as an expression produces only logical values (0 or -1), you can safely use NOT. Expressions such as IF NOT (A = B) THEN GO TO 10 or IF NOT (X 5 AND Y 8) THEN GO TO 10 are fine. They only deal with logical operators. The value inside the parentheses will…"
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authors: "David Lubar"
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pubdate: "May/June 1981"
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---

# More Truth in Programming

As long as an expression produces only logical values (0 or -1), you can safely use NOT. Expressions such as IF NOT (A = B) THEN GO TO 10 or IF NOT (X 5 AND Y 8) THEN GO TO 10 are fine. They only deal with logical operators. The value inside the parentheses will be either zero or minus one. But if other integers enter the expression, it’s not safe to use NOT.