Tom's Lisp

This document contains a list of all the standard Tom's Lisp functions.

Integer Operations
Call	Where Defined	More Info	Description
(+ i1 . . .)	Builtin	Basic Input	Add integer values.
(- i1 i2)	Builtin	Basic Input	Subtract integer values.
(* i1 . . .)	Builtin	Basic Input	Multiply integer values.
(/ i1 i2)	Builtin	Basic Input	Divide integer values. Integer result with no fractional part
(% i1 i2)	Builtin	Basic Input	Modulus.
(< i1 i2)	Builtin	Conditionals	Less than.
(> i1 i2)	Builtin	Conditionals	Greater than.
(<= i1 i2)	Builtin	Conditionals	Less than or equal.
(>= i1 i2)	Builtin	Conditionals	Greater than or equal.
(= i1 i2)	Builtin	Conditionals	Equal.
(!= i1 i2)	Builtin	Conditionals	Not equal.
List Operations
Call	Where Defined	More Info	Description
(car lis)	Builtin	Lists	Return the first element of list (or pair) lis.
(cdr lis)	Builtin	Lists	Return the remainder of the list lis after the first element. If lis is a pair, return the second part.
(cons x1 x2)	Builtin	Lists	Combine x1 and x2 as a pair, or add x1 to the front of list x2.
(length lis)	Init File	Lists	Return the length of list lis.
(first n lis)	Init File	Lists	Return the first n items from lis.
(last n lis)	Init File	Lists	Return the last n items from lis.
(first-but n lis)	Init File	Lists	Return the list lis absent its last n elements.
(last-but n lis)	Init File	Lists	Return the list lis absent its first n elements.
(nth n lis)	Init File	Lists	Return the n-th element (zero-based) of list lis.
Type Identification
Call	Where Defined	More Info	Description
(null? x)	Builtin	Conditionals	Tell if the argument is nil (empty list).
(pair? x)	Builtin	Conditionals	Tell if the argument is a pair (result of cons, most often a non-empty list.)
(id? x)	Builtin	Conditionals	Tells if the argument is an identifier.
(int? x)	Builtin	Conditionals	Tells if the argument is an integer.
(str? x)	Builtin	Conditionals	Tells if the argument is a string.
(builtin? x)	Builtin	Conditionals	Tells if the argument is a builtin function.
(lambda? x)	Builtin	Conditionals	Tells if the argument is a function (result of the lambda operator
(macro? x)	Builtin	Conditionals	Tells if the argument is a macro (result of the macro operator
(functional? x)	Init File	Conditionals	Tells if the argument is something that can be called with a parameter list as a function is. These are any of the last three types.
Comparison and Boolean Operations
Call	Where Defined	More Info	Description
(eq? x1 x2)	Builtin	Conditionals	Compare the physical locations of the objects x1 and x2. Return true if they are the same (i.e., are the same physical object.) Objects having the same value will not be considered eq? if they are stored in different places. Use equal? instead.
(equal? x1 x2)	Builtin	Conditionals	Tells if x1 and x2 have the same type and value.
(not x)	Init File	Conditionals	Return the logical inverse of x.
(and x1 . . . xn)	Init File	Conditionals	Return true if all xi values are true. The xi's are evaluated left-to-right, short-circuit.
(or x1 . . . xn)	Builtin	Conditionals	Evaluate the xi values from left to right and return the first one which is not nil, otherwise return nil.
(nand x1 . . . xn)	Init File	Conditionals	Return the not of the and.
(nor x1 . . . xn)	Init File	Conditionals	Return the not of the or.
Controlling Evaluation
Call	Where Defined	More Info	Description
(quote x)	Builtin	Quoting & Evaluation	Return x without evaluation.
(eval x)	Builtin	Quoting & Evaluation	Evaluate x and return.
(apply f lis )	Init File	Quoting & Evaluation	Run the function f with the parameters lis.
(if cond x1 x2)	Init File	Conditionals	Evaluate cond. If it yields a true value, evaluate and return x1, else evaluate and return x2.
(cond ( p1 x1 ) . . . ( pn xn ))	Builtin	Conditionals	Evaluate each pi in order until one is true. Then evaluate and return the corresponding xi. If no pi is true, return nil.
(begin x1 x2 . . . xn)	Builtin	Conditionals	Evaluate each of x1 through xn in order, and return the result from xn.
Definitions and Scope
Call	Where Defined	More Info	Description
(set id x)	Builtin	Definitions	Set the identifier id to the value x in the current context.
(setq id x)	Init File	Definitions	Same as set, but the identifier is automatically quoted.
(define ( id p1 . . . ) expr)	Init File	Functions	Define a function id with parameters p1 dots and body expr.
(define id x)	Init File	Definitions	Same as setq.
(scope expr1 . . . exprn)	Builtin	Definitions	Evaluate the expressions expr1 . . . exprn, in a new scope, and return the value of exprn.
(let ( ( i1 x1 ) . . . ( in xn ) ) expr)	Init File	Definitions	Evaluate expr in a new scope after sequentially evaluating each xk and assigning it to ik.
Functions And Macros
Call	Where Defined	More Info	Description
(lambda parms expr)	Builtin	Functions	Create a function with the parameter list given by parms and the body given by expr. The parms may be a list of identifiers or a single identifier. In the first case, the function must be called with a list of arguments of the same length as parms and each argument is bound to each parameter in the same order. If parms is a single identifier, the entire list of arguments is bound to it. Arguments are evaluated, the body is run, and its value returned.
(macro parms expr)	Builtin	Macros	Create a macro closure. The parms may take the same forms as for lambda. When called, arguments are not evaluated, but the result of the body is.
String Operations
Call	Where Defined	More Info	Description
(strlen x)	Builtin	Strings	Returns the length of string x.
(string-length x)	Init File	Strings	Returns the length of string x (an alias for strlen).
(concat x1 x2)	Init File	Strings	Concatinate strings x1 and x2.
(string-append x1 x2)	Init File	Strings	Concatinate strings x1 and x2 (an alias for concat).
(substr x i1 i2)	Init File	Strings	Return the substring of string x starting at i1 (zero-based) and of length i2.
(chr i)	Builtin	Strings	Returns a string containing the single character with the ascii value of i.
(ord x)	Builtin	Strings	Return the ascii value of the first character of the string x.
(shatter x)	Builtin	Strings	Return a list of single-character strings, each being the characters of string x, in the same order.
(collect x)	Builtin	Strings	Take a list of string x and return their concatination.
Errors and Exceptions
Call	Where Defined	More Info	Description
(error code descr)	Builtin	Exceptions	Create and return an error object containing the integer code code and string description descr. This is essentially a throw operation.
(catch x1 x2 . . . xn)	Builtin	Exceptions	Evaluate x1 through xn in order. If there is no exception, return the pair consisting of #t and the value of xn. If not, return (nil . (code. descr)), where code and descr are the integer and string contents of the excpetion.
(succeeds x1 x2 . . . xn)	Init File	Exceptions	Evaluate x1 through xn in order. If there is no exception, return #t, otherwise return nil.
(fails x1 x2 . . . xn)	Init File	Exceptions	Evaluate x1 through xn in order. If there is no exception, return nil, otherwise return #f.
(try expr (e1 x1) (e2 x2) . . . (en xn))	Init File	Exceptions	Evaluate expr. If no exception is thrown, return the result. Otherwise, scan the ek values left to right for a match. If one is found, evaluate xk and return its value. Otherwise, rethrow the original exception. An ek matches if it is the atom #t, if it is an atom which evalutes to the integer code of the thrown exception, or if it is a pair which evaluates to true. During evaluation of any ek or xk, the symbols ERROR and MESSAGE are bound to the code and message part, respectively, of the thrown exception.
Miscellaneous
Call	Where Defined	More Info	Description
(exit i)	Builtin	Basic Input	Immediately exit the interpreter passing the indicated exit code to the O/S.
(quit )	Init File	Basic Input	Immediately exit the interpreter with code 0.