~~Title: Evaluator Dynamic Button State~~
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You can use the evaluator with the various [[:reference:command_reference:command_modifier_reference|command modifiers]] that affect the state of toolbar buttons:

  * **@hideif** / **@showif** - dynamically hide or show the button
  * **@disableif** / **@enableif** - dynamically disable or enable the button
  * **@toggle** - control whether the button appears checked/selected or unchecked/unselected

Note that these modifiers can also be used [[:reference:command_reference:command_modifier_reference#@icon|without the evaluator]], so to use the evaluator you must begin the expression with a `=` character.

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The return value from the evaluation expression will be used to determine the state. The meaning depends on the modifier in question:

  * **@hideif** - return **true** to hide the button, **false** to show it
  * **@showif** - return **true** to show the button, **false** to hide it
  * **@disableif** - return **true** to disable the button, **false** to enable it
  * **@enableif** - return **true** to enable the button, **false** to disable it
  * **@toggle** - return **true** if the button should be checked/selected, **false** otherwise