Characters
Valid ASCII characters supported will vary from computer to computer. Some
installations use only 7-bit or 128 characters to represent the keys on the
keyboard. Other installations provide an additional 128 characters for diacritical
marks, line drawing, GREEK, and other symbols. nu/TPU assumes the following
groups will be valid on every machine.
ASCII Range Description
0 - 31 Control characters
32 Space
33-64 Numbers and special characters
65-122 Lowercase and uppercase letters
123-126 Special characters
127 Delete
128-255 Extended ASCII characters
Special Characters
nu/TPU uses several characters for special purposes. The following lists the
special characters and their nu/TPU specific functions.
Character Name Function
& Ampersand Pattern concatenation operator
‘ Apostrophe String delimiter
* Asterisk Arithmetic multiplication operator
@ At Symbol Partial pattern assignment, pattern assignment operator
) Close Parenthesis End list
: Colon Value assignment operator
, Comma Separates parameters
$ Dollar Sign Word separator with an identifier
= Equal Sign Relational equal to operator, value assignment operator
! Exclamation Point Comment
< Left Angle Bracket Relational less than operator
{ Left Brace Start array element
[ Left Bracket Begin case label
- Minus Sign Arithmetic subtraction, unary minus operator
( Open Parenthesis Begin list
% Percent Sign Conditional compilation, numeric radix assignment
+ Plus Sign Arithmetic addition, unary plus, or string concatenation
“ Quotation Mark String delimiter
> Right Angle Bracket Relational greater than operator
} Right Brace End array element
] Right Bracket End case label
; Semicolon Statement terminator
/ Slash Arithmetic division operator
_ Underscore Word separator within an identifier
| Vertical Bar Pattern alternation operator
Operators by Type
ARITHMETIC
+ Addition, unary plus
- Subtraction, unary minus
/ Division
* Multiplication
STRING
+ String concatenation
* String replication
RELATIONAL
= Equal
<> Not equal
< Less than
> Greater than
<= Less than or equal
>= Greater than or equal
PATTERN
@ Partial pattern assignment
+ Pattern concatenation
& Pattern linkage assignment
| Pattern alternation
LOGICAL
AND Boolean and
NOT Boolean negation
OR Boolean or
XOR Boolean exclusive or
ASSIGNMENT
:= Value assignment
Operator Precedence
nu/TPU makes use of several standard operators to perform arithmetic,
relational, pattern, logical, and assignment functions. Operators are assigned the
following precedence. Within an expression, the operators are evaluated in order;
the highest precedence is evaluated first. Parentheses may be used to determine
the evaluation order.
Highest Unary -, Unary +
NOT
*, /, AND
@@, &, +, -, |, OR, XOR
=, <>, <, <=, >, >=
Lowest :=
Entering Control Characters
nu/TPU can tie control characters to editing functions and allow them to be
entered into the buffer text. To put a control character into the active buffer,
use the ASCII built-in and the ASCII value for the control character you wish
to enter. The following line enters the form-feed character into the buffer.
COPY_TEXT (ASCII (12));
The si interface allows control characters to be entered from keyboard keys. After
pressing CTRL-V, the next key pressed will be inserted. To insert the form-feed
character, press CTRL-V then CTRL-L.
Character Usage