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Verb Information Functions

verb_info

Description: Retrieves basic information about a verb on an object.
Arguments:

  • : The object that has the verb object
  • : Either the verb name or a positive integer representing the verb's position in the verb list (1-based) verb-desc

Returns: A list containing three elements:

  1. The owner of the verb (object reference)
  2. A string representing the permission flags: 'r' (read), 'w' (write), 'x' (execute), 'd' (debug)
  3. A string containing the verb names (aliases) separated by spaces

Note: Requires read permission on the verb.

set_verb_info

Description: Changes the permission information for a verb.
Arguments:

  • : The object with the verb to modify object
  • : Either the verb name or a positive integer representing the verb's position (1-based) verb-desc
  • : A list containing permission information: [owner, permissions, names]
    • : The new owner of the verb (object reference) owner
    • : A string containing the permission flags (combination of 'r', 'w', 'x', 'd') permissions
    • : A string containing space-separated verb names/aliases names

info

Returns: none
Note: Requires appropriate permissions to modify the verb.

Verb Arguments Functions

verb_args

Description: Retrieves information about a verb's argument specification.
Arguments:

  • : The object that has the verb object
  • : Either the verb name or a positive integer representing the verb's position (1-based) verb-desc

Returns: A list containing three elements:

  1. The direct object specification (e.g., "this", "none", "any")
  2. The preposition (e.g., "with", "at", "in front of")
  3. The indirect object specification (e.g., "this", "none", "any")

Note: Requires read permission on the verb.

set_verb_args

Description: Changes the argument specification for a verb.
Arguments:

  • : The object with the verb to modify object
  • : Either the verb name or a positive integer representing the verb's position (1-based) verb-desc
  • : A list containing argument specifications: [dobj, prep, iobj]
    • : String specifying direct object behavior dobj
    • : String specifying the preposition prep
    • : String specifying indirect object behavior iobj

args

Returns: none

Note: Requires appropriate permissions to modify the verb.

Verb Code Functions

verb_code

Description: Retrieves the source code of a verb.
Arguments:

  • : The object that has the verb object
  • : Either the verb name or a positive integer representing the verb's position (1-based) verb-desc
  • : Optional boolean indicating whether to fully parenthesize the code (default: false) fully-paren
  • indent: Optional integer specifying indentation amount (default: 0)

Returns: A list of strings, each representing a line of the verb's source code
Note: Requires read permission on the verb and programmer bit.

set_verb_code

Description: Changes the source code of a verb. Arguments:

  • object: The object with the verb to modify
  • verb-desc: Either the verb name or a positive integer representing the verb's position (1-based)
  • code: A list of strings, each representing a line of the verb's source code
  • verbosity: (Optional) Controls error output detail level (default: 2)
    • 0 - Summary: Brief error message only
    • 1 - Context: Message with error location (graphical display when output_mode > 0)
    • 2 - Detailed: Message, location, and diagnostic hints (default)
    • 3 - Structured: Returns error data as a map for programmatic handling
  • output_mode: (Optional) Controls error formatting style (default: 0)
    • 0 - Plain text without special characters
    • 1 - Graphics characters for visual clarity
    • 2 - Graphics with ANSI color codes

Returns:

  • On success: empty list {}
  • On compilation failure with verbosity 0-2: list of formatted error strings
  • On compilation failure with verbosity 3: map containing structured error data (use format_compile_error() to format)

Note: Requires appropriate permissions to modify the verb and programmer bit.

Examples:

// Basic usage with default detailed errors
set_verb_code(#123, "test", {"return 1 + ;"});
=> {"Parse error at line 1, column 12:", "  return 1 + ;", "             ⚠", ...}

// Get structured error data for custom handling
err = set_verb_code(#123, "test", {"return 1 + ;"}, 3);
=> [type -> "parse", message -> "unexpected ';'", line -> 1, column -> 12, ...]

// Format the structured error with custom verbosity
formatted = format_compile_error(err, 0);  // Summary only
=> {"Parse error at line 1, column 12: unexpected ';'"}

Verb Management Functions

add_verb

Description: Adds a new verb to an object.
Arguments:

  • : The object to add the verb to object
  • : A list containing permission information (same format as in ) infoset_verb_info``
  • : A list containing argument specifications (same format as in ) argsset_verb_args``

Returns: none
Note: Requires appropriate permissions to add verbs to the object and programmer bit.

delete_verb

Description: Removes a verb from an object.
Arguments:

  • : The object to remove the verb from object
  • : Either the verb name or a positive integer representing the verb's position (1-based) verb-desc

Returns: none
Note: Requires ownership of the verb or the object and programmer bit.

Error Formatting Functions

format_compile_error

Description: Formats a structured compilation error map into human-readable text. Arguments:

  • error: Map containing compilation error data (from set_verb_code() or eval() with verbosity 3)
  • verbosity: (Optional) Controls output detail level (default: 2)
    • 0 - Summary: Brief error message only
    • 1 - Context: Message with error location (graphical display when output_mode > 0)
    • 2 - Detailed: Message, location, and diagnostic hints
  • output_mode: (Optional) Controls formatting style (default: 0)
    • 0 - Plain text without special characters
    • 1 - Graphics characters for visual clarity
    • 2 - Graphics with ANSI color codes

Returns: List of formatted error strings

Note: Use this function to format structured error maps returned by set_verb_code() or eval() when called with verbosity 3.

Example:

// Get structured error data
err = set_verb_code(#123, "test", {"return 1 + ;"}, 3);

// Format with different verbosity levels
summary = format_compile_error(err, 0);
=> {"Parse error at line 1, column 12: unexpected ';'"}

detailed = format_compile_error(err, 2);
=> {"Parse error at line 1, column 12:", "  return 1 + ;", "             ⚠", ...}

// Format with color for terminal display
colored = format_compile_error(err, 2, 2);

Advanced Verb Functions

disassemble

Description: Provides a detailed breakdown of the compiled bytecode for a verb.
Arguments:

  • : The object that has the verb object
  • : Either the verb name or a positive integer representing the verb's position (1-based) verb-desc

Returns: A list of strings showing the internal compiled representation of the verb
Note: Output format is not standardized and may change between versions.

respond_to

Description: Checks if an object has a verb with a specific name.
Arguments:

  • : The object to check object
  • : The name of the verb to check for verb-name

Returns:

  • If the object doesn't have a verb with that name: (false) 0
  • If the caller controls the object or the object is readable and the verb exists: a list containing the location of the verb and its names
  • If the caller doesn't control the object but the verb exists: (true) 1

Verb Permissions Explained

Verbs in this system use a permission model based on the following flags:

  • (read): Controls who can read the verb's code r
  • w (write): Controls who can modify the verb's code
  • (execute): Controls who can execute the verb x
  • (debug): Controls whether the verb runs in debug mode d

These permissions are represented as a string (e.g., "rwxd" for all permissions, "rx" for read and execute only).

prepositions

Description: Returns a list of all valid prepositions that can be used in verb argument specifications.

Arguments: None

Returns: A list of preposition entries. Each entry is a list containing three elements:

  1. The preposition ID (1-indexed, 1-16)
  2. The canonical/short form (single preposition string)
  3. A list of all valid alternate forms for that preposition

Example:

prepositions()
=> {
  {1, "with", {"with", "using"}},
  {2, "at", {"at", "to"}},
  {3, "in-front-of", {"in front of", "in-front-of"}},
  {4, "in", {"in", "inside", "into"}},
  ...
  {16, "named", {"named", "called", "known as"}}
}

Note: This is useful for introspection and for code that needs to validate or work with prepositions programmatically.

Verb Arguments Specification

The verb arguments specification consists of three components:

  1. Direct Object (dobj) - Can be one of:

    • "this" - Object must match the verb's location
    • "none" - No object expected
    • "any" - Any object is acceptable

  2. Preposition (prep) - Specifies the preposition, like "with", "at", "in", etc. Use prepositions() to get a list of valid values.

  3. Indirect Object (iobj) - Same options as Direct Object

These specifications control how the parsing system matches player commands to verbs.