Boolean Negation "!"

<number> = !<number>

Boolean / logical Operators: Boolean Negation "!"negation.

Flow control: if … then
Flow control: if … thenIf the Vipsi command syntax: Arguments
Glossary: Argumentsargument Glossary: number, num_valnumber is evaluated as true (non-zero) Operators: Boolean Or with Variable "||="
Operators: Bitwise Or with Variable "|="
Operators: Bitwise Or "|"
Operators: Boolean Or "||"or false Operators: Boolean And with Variable "&&="
Operators: Bitwise And with Variable "&="
Operators: Bitwise And "&"
Operators: Boolean And "&&"and Flow control: if … then
Flow control: try … thenthen List functions: thisthis boolean Glossary: Valuevalue is negated, resulting in '0' Operators: Boolean Or with Variable "||="
Operators: Bitwise Or with Variable "|="
Operators: Bitwise Or "|"
Operators: Boolean Or "||"or '1'.

Flow control: if … then
Flow control: if … thenIf the supplied Glossary: Valuevalue is a Data Types: Text
Item selector "[]": Text
Glossary: text, text_valtext, Flow control: if … then
Flow control: try … thenthen it is automatically evaluated as a Glossary: number, num_valnumber.

e.g.:

Flow control: if … thenif !Numeric functions: existsexists(boo) Numeric functions: log
Numeric functions: loge
Instructions: loglog "Glossary: Variable, var_refvariable boo is missing" Flow control: if … then
Flow control: try … thenthen;