PRINT

Syntax

PRINT [#chan,] *[ [separator] [strgi$ separator] vari]* or

PRINT *[ [#chan,] [separator] [strgi$ separator] vari]* (THOR XVI & Minerva v1.97+ only)

Location QL ROM

This command will send a string of bytes to the specified channel (default #1).

If any variables (var) are specified, the contents of those variables are PRINTed in the specified channel.

If the channel is a window, the characters printed appear at the current text cursor position, in the current INK colour on the current STRIP colour, and will also be affected by the settings of CSIZE, UNDER, FLASH and OVER.

If you tell PRINT to use an unset variable, an asterisk (‘*’) will be PRINTed on screen rather than an error being reported (except on SMS where an unset variable is given the value 0 (if a numeric variable) or ‘’ for a string). Beware, however that if you try to use an unset variable in a calculation inside the PRINT statement, an ‘Error in Expression’ error will be generated, for example:

a=10 : PRINT 'A is :'! a ,'B is :'! b : PRINT 'A*B is :' !a*b

If a channel is specified, this must be followed by a comma. It may however also be followed by one or more separators, as with INPUT.

At the end of the PRINT command, the text cursor is placed at the start of the next print line (unless an end separator of ‘!’, ‘' or ‘;’ is used). When using a separator of ‘!’, TO or ‘,’ on a non-window channel, the PRINT statement will always assume the end of each line to be the number of characters specified with the WIDTH command, thus allowing you to format your output on a printer, for example.

Example

The following procedure allows you to print text to a given channel without splitting words when the text wraps onto the next line:

100 DEFine PROCedure PRINT_TEXT(ch,txt$)
110   LOCal print_loop
120   REPeat print_loop%
130     IF LEN(txt$)=0:PRINT #ch:RETurn
140     I%=' ' INSTR txt$
150     IF I%=0:PRINT #ch!!txt$:RETurn
160     PRINT #ch!!txt$(1 TO I%-1)!
170     IF I%<LEN(txt$):txt$=txt$(I%+1 TO):ELSE txt$=''
180   END REPeat print_loop%
190 END DEFine

Try:

WINDOW #1,50,100,32,16: PRINT_TEXT #1,'This is a test line'

Compare:

PRINT #1,'This is a test line'

NOTE 1

Version 6.40 of the THOR XVI ROM can crash if you try to use PRINT with the ‘!’ separator in a non-window channel.

NOTE 2

The THOR XVI (all versions) and non-Minerva ROMs (unless SMS is installed) have problems with the concatenation of values which should produce an ‘Overflow Error’. For example:

PRINT 'hello'&(1/0)

may crash the computer rather than producing an overflow error.

NOTE 3

PRINT can only show a maximum of six integer digits. If a number is larger than this, it will be represented by the E function (eg. 1E2 is the same as 100). If on the other hand, the figure is a floating point, then the QL can cope with seven digits excluding the decimal point, eg. 123.4567. Any more digits will cause the number to be rounded up or down as appropriate.

MINERVA NOTE

v1.97+ allows different channels part way through statement as per THOR XVI.

THOR XVI NOTE

Version 6.41 of the THOR XVI allows you to put channel numbers part way through a statement, for example:

PRINT 'Name:'!name$ \#0; 'Address:' !address$

instead of:

PRINT 'Name '!name$ : PRINT #0;'Address:'!address$

CROSS-REFERENCE

See also INPUT which contains a description of the different types of separators. Please also see WIDTH. TO has other meanings - see TO. VG_PRINT allows you to print using scalable fonts on screen. CHAR_USE and CHAR_DEF allow you to alter the fonts used for printing characters on screen.