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Good day, I've been searching the web for the meaning of these operators: $\gtrdot$ and $\lessdot$.

The reason I ask is because they are used symbols that look like operators and in the Katex documentation for supported functions they are listed as binary operators.

If this question is already answered please direct me and I will delete this post. Thank you.

Blue
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Juli TR
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1 Answers1

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$\gtrdot$ and $\lessdot$ are operators belonging from the Operator Precedence Languages.

Given two terminals $a,~ b$, for any non-terminals $A, ~B,~ C$ and mixed terminal/non-terminal strings $α,~ β, ~γ$, we say
$(i)~~$ $\bf a$ yields precedence to $\bf b$ $~(a \lessdot b)~$ if there exists a rule $~A → αaCβ~$, s.t. a string $~Baγ~$ or $~aγ~$ derives from $~C~$ in any number of passes;
$(ii)~~$ $\bf a$ is equal in precedence to $\bf b$ $~(a \doteq b)~$ if there exists a rule $~A → αaCbβ~$ or $~A → αabβ~$;
$(iii)~~$ $\bf a$ takes precedence over $\bf b$ $~(a \gtrdot b)~$ if there is a rule $~a → αCbβ~$, s.t. $~γaB~$ or $~γa~$ derives from $~C~$.

In practice, $~a \lessdot b~$ if $b$ is the beginning of $a$ right hand side (rhs); $~(a \doteq b)~$ if they belong to the same rhs; $~(a \gtrdot b)~$ if a is the end of a rhs.

For more details you may find the following references:

$1.~~$ "Precedence Automata and Languages" by Lonati V., Mandrioli D., Pradella M.
$2.~~$ "Word- and Tree-Based Temporal Logics for Operator Precedence Languages" by Michele Chiari, Dino Mandrioli, and Matteo Pradella
$3.~~$ "Mathematical Operators"
$4.~~$ Operator-precedence grammar

nmasanta
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