class Tag

Identity provider for Cells and Builtins.

Tags are one of:

• 'blank' ([?], to be auto-assigned by the Copilot)
• literal ([1])
• virtual ([str], won't be tracked)
• cloned ([X.Y], obtained by cloning Y with parent X)

index

members

• tag\last()  – obtain the registered value of the last eval-cycle.
• tag\clone(parent)  – create a copy of this tag scoped to a parent tag.
• tag\ident()  – get a globally-unique identifier for this tag

static functions

• Tag.parse(num)  – parse a Tag (for Lpeg parsing).

internals for `registry`

• tag\index()  – get a unique index value for this Tag.
• tag\set(value)  – callback to set value for blank tags.
• tag.registry  – the Registry associated with this Tag
• tag.pending  – whether this Tag is newly assigned this tick

details

members

• tag\last()  – obtain the registered value of the last eval-cycle.
  Obtain the value that was previously registered for this tag on the last eval-cylce.

  returns:

  1. (optional any)
• tag\clone(parent)  – create a copy of this tag scoped to a parent tag.
  Will mark blank tags for auto-assignment at the end of the eval cycle.

  parameters:

  • parent (Tag): the parent tag

  returns:

  1. (Tag): the cloned tag
• tag\ident()  – get a globally-unique identifier for this tag
  prepends the module name to the tag string

  returns:

  1. (string): a unique string

static functions

• Tag.parse(num)  – parse a Tag (for Lpeg parsing).

  parameters:

  • num (string): the number-string

  returns:

  1. (Tag)

internals for `registry`

• tag\index()  – get a unique index value for this Tag.
  The index is equal to value for simple tags and a path-like string for cloned tags.

  returns:

  1. (number or string)
• tag\set(value)  – callback to set value for blank tags.
  value may be blank to reassign duplicate tags.

  parameters:

  • value (optional number)
• tag.registry  – the Registry associated with this Tag
  • registry (Registry)
• tag.pending  – whether this Tag is newly assigned this tick
  • pending (bool)