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title: "An Introduction to Expression Evaluation"
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modified_at: "2024-06-23T01:05:03+00:00"
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excerpt: "In the Sinclair 8K ROM program of the ZX80/81 the \"expression evaluator\" is to be found at 0F55-111Bh (improved 8K ROM) and forms an essential part of the program. A study of the fundamental parts of the \"expression evaluator\" can be very useful as it enables Basic programmers to understand many of the limitations and…"
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# An Introduction to Expression Evaluation

In the Sinclair 8K ROM program of the ZX80/81 the “expression evaluator” is to be found at 0F55-111Bh (improved 8K ROM) and forms an essential part of the program. A study of the fundamental parts of the “expression evaluator” can be very useful as it enables Basic programmers to understand many of the limitations and quirks of the Sinclair Basic.