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T3X - A Minimum Procedural Language
Version 8.1.5, Online Edition
Copyright(C) 1996-2004
Nils M Holm
 
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2.6.5 Bit Operators
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2.6.7 Conjunctions and Disjunctions

2.6.6 Relational Operators

Relational operators are used to compare two operands. The relation between the operands is expressed as a truth value: all these operators return truth (-1), if their meaning applies to their operands and otherwise they return falsity (0). The following relational operations exist (.X denotes the unsigned value of X):

Operator Description
A < B A is less than B
A > B A is greater than B
A <= B A is less than or equal to B
A >= B A is greater than or equal to B
A .< B .A is less than .B
A .> B .A is greater than .B
A .<= B .A is less than or equal to .B
A .>= B .A is greater than or equal to .B
A = B A is equal to B
A \= B A is not equal to B

Note: the operators expressing equivalence (=, \=) have a lower precedence than operators expressing ordering (> , <, >=, <=, .<, .>, .<=, .>=). For example,

A < B = C < D

is equal to

(A<B) = (C<D)

Consequently, the equation sign may be interpreted as `logical equivalence' when used between comparisons: the above expression evaluates to true, if either

(A<B) AND (C<D)

or

\(A<B) AND \(C<D)

applies. Since the inequation operator \= has the same precedence as =, it may be used as a negative logical equivalence operator (aka an Exclusive OR):

A<0 \= B<0

becomes true, if either A or B is negative. If the truth values of the comparisons A<0 and B<0 are equal, the expression yields the result `false'.

Note that any value may be considered a truth value in T3X. Everything but the zero value is interpreted as `truth', and only 0 may be used to express the `false' value.

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2.6.5 Bit Operators
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2.6.7 Conjunctions and Disjunctions