Bang prefixing to reverse default actions
Some builtins support a bang prefix, !, which provides a
shorthand negative action to default behavior. For example,
set defines a variable where as !set will
undefine a variable.
Sometimes the shortcut will be logical, like a not
operator, as is the case with and where typically each
result has to equal true normally or
false if used in !and.
Sometimes the shortcut will be more philosophical, such as with
config where normal operations is to query or set
configuration but !config resets the configuration to
defaults (thus operating the same as config default).
Please read the respecting commands doc for details on whether it supports a bang prefix and what the behavior of that prefix is.
set):
Define a variable (typically local) and set it’s valueand): Returns true or false
depending on whether multiple conditions are metor): Returns true or false
depending on whether one code-block out of multiple ones supplied is
successful or unsuccessful.!): Reads
the stdin and exit number from previous process and not’s it’s
conditionconfig): Query or define Murex runtime settingsThis document was generated from gen/user-guide/bang-prefix_doc.yaml.
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