substitute

Applies a Lexicon to an Expression resulting in recursive Operator replacement, without using definitions from the enclosing scope.

Input

{lexicon} {expression}

Output

{lexicon} {evaluation}

Examples

substitute {A{1}} {A}

{A{1}}{1}

substitute {A{1}} {do{A}}

{A{1}}{do{A}}

Implementation

Om::Language::Operation::SubstituteOperation

Looking up an Operator in the Lexicon has the following possible outcomes:

• The Operator not found:
  • The default (empty Operator mapping), if any, is used.
• The Operator is found, but has no mapping:
  • The Operator is considered undefined, and no further checking is done.
• The Operator is found, and has an Operand mapping:
  • The Operator is replaced with the Operand Program.