ranges - integer range functions library
forth integer range library. Allows definition and manipulation of
ranges of integers. Defines a recognition function so that standard
range notation may be used, i.e., [<from>..<to>], where <from> and
<to> are integer values.
- struct.type RANGE ( from to -- )
- The range defined as a structure type thus structure operations
are allowed (e.g. sizeof) and access of the interval range numbers.
May be used to create range variables or fields in "structures".
The "RANGE" variable may be accessed using the double number
memory access functions; "2@", and "2!". The structure type contains
two private fields, "+from" and "+to".
- : range ( from to -- )
- Used in the following form to create a range constant:
( -- from to)
When the range constant is used it will produce the values.
Any double variable may used as an integer range if the values are
in the right order, "from".."to", and may be accessed and manipulated
with the double number stack and memory access functions.
- vocabulary ranges ( -- )
- Integer range extensions vocabulary. Include into the vocabulary
search structure, "context", to allow access to these extensions.
- : ?intersection-range ( from1 to1 from2 to2 -- bool)
- Returns "true" if there exists an intersection range between
the two ranges defined by "from1".."to1" and "from2".."to2"
- : ?map-range ( from to block[index -- bool] -- )
- Used in the following form:
Conditional map function on a range. The block is called for
each value of the range starting with "from" and ending with "to"
until the block returns "true". The block receives the index as a
parameter and should return a boolean value.
- : ?member-range ( x from to -- bool)
- Returns "true" if the value is within the range defined by
"from" and "to" else "false".
- : ?range ( str -- [from to true] or [str false]) recognizer
- The integer range recognition function. Is called automatically
by "interpret" when a literal is encountered and the "ranges"
vocabulary is member of the search chain. The recognizer
function will return "true" if the parameter string is of
and the relationship between the numbers is correct, i.e.,
is greater or equal to
- : intersection-range ( from1 to1 from2 to2 -- from3 to3)
- Given two ranges defined by "from1".."to1" and "from2".."to2"
returns their intersection. This function does not check if
an intersection exists. This may be done with the word
- : map-range ( from to block[index -- ] -- )
- Used in the following form:
Map function on a range defined by "from" and "to". The block is
called for each value of the range starting with "from" and ending
with "to". The block receives the index as a parameter.
- : size-range ( from to -- num)
- Returns the size of the range by calculating "to" - "from" + 1.
Private definitions in the
- long +from ( range -- addr) private
- Returns address to "from" value of a "RANGE" structure.
- long +to ( range -- addr) private
- Returns address to "to" value of a "RANGE" structure.
An example showing how to used the integer ranges extensions:
[0..15] range small-numbers
small-number block[ ( index -- ) . ]; map-range cr
10 [-128..127] ?member-range . cr
The function list is sorted in ASCII order. The type and mode of
the entries are indicated together with their parameter stack effect.
Copyright (C) 1990 Mikael R.K. Patel
Permission is granted to make and distribute verbatim copies
of this manual provided the copyright notice and this permission
notice are preserved on all copies.
Permission is granted to copy and distribute modified versions
of this manual under the conditions for verbatim copying,
provided also that the section entitled "GNU General Public
License" is included exactly as in the original, and provided
that the entire resulting derived work is distributed under
the terms of a permission notice identical to this one.
Permission is granted to copy and distribute translations of
this manual into another language, under the above conditions
for modified versions, except that the section entitled "GNU
General Public License" may be included in a translation approved
by the author instead of in the original English.
Mikael R.K. Patel
Computer Aided Design Laboratory (CADLAB)
Department of Computer and Information Science
S-581 83 LINKOPING