Lending

Axioms:

• A muttable lend (@) can only be created if all of the following:
  • The variable is defined
  • No immutable lends exist on the variable already
  • No mutable lends exist on the variable already (though a variable referring to lent value can be mutably lent)
  • The variable itself is not a constant
• An immutable lend ($) can only be created if all of the following:
  • The variable is defined
  • No mutable lends exist on the variable

Syntax

lend ::= ( "@" | "$" ) <variable>

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Last update: November 15, 2022