Mentor

Personal Computer News

Features 3/5

Documentation 2/5

Performance 3/5

Usability 3/5

Reliability 5/5

Overall Value 3/5

Ted Ball 3/5

NAME: Mentor APPLICATION: Basic program editor SYSTEM: ZX Spectrum, 16K, or 48K PRICE: £8.95 PUBLISHER: JK Godsen Software, [redacted] FORMAT: Cassette OUTLETS: Mail order WHAT'S MY LINE? Ted Ball meets his Spectrum mentor and asks if it's a toolkit or an editing packing. When you are writing a Basic Wprogram you often want better editing facilities than are provided in your computer. Mentor, for the 16K or 48K ZX Spectrum, gives you a number of block and global editing commands to supplement the Spectrum's built-in line editor. FEATURES The editing functions provided in Mentor are: Renumber: This changes the line numbers so that they are in a neat sequence, and also changes the line numbers in GOTO and GOSUB statements. However it will not change the GOTOs and GOSUBs if the line number referred to does not exist or if the line number is specified by an expression. Block text operations: These functions allow you to move a block of lines to a different part of the program, copy a block of lines to a different part of the program, or delete a block of lines. The operations are normally followed by an automatic renumber, but you can suppress this if you wish. Search operations: With these functions you may search the program for any string, which can include Basic keywords; search for GOTO and GOSUB statements that contain a line number: or search for GOTO and GOSUB statements that contain an expression. If the search is successful the line is displayed, and you can continue to search the rest of the program. String substitution: This allows you to specify target string and a replacement string. Also, Mentor will search the program, displaying the lines containing the target string and give you the option of substituting the replacement string at each occurrence. Variable dump: This allows you to display the program variables in the form they are stored in the Spectrum (as explained in Chapter 24 of the Spectrum manual). The variable name is displayed in ASCII characters but the rest of the data is displayed as the hexadecimal values of individual bytes. PRESENTATION The cassette is clearly labelled and has two copies of the Mentor program recorded on one side. The documentation consists of three pages copied from a typed original. Although it describes all the functions included in Mentor and gives the syntax for the commands, it is not easy to follow. GETTING STARTED Getting Mentor up and running is rather a tedious job that could have been made easier. First you have to load the machine code, then run it by typing in a USR command. Then you have to work through a title screen and five screens of instructions. It's the fifth screen that contains the instructions for actually getting Mentor relocated and running. IN USE Once you have Mentor loaded and running you can type in or load your program from tape, and use the Mentor functions for editing. However, it takes a little time to get used to the commands, as they are not clearly explained in the documentation and you have to experiment to find out exactly how the commands operate. For example, to move a block of text you have to type in "MTX a,b,c" and the documentation says that 'This moves the text between lines be to line a location'. However, it is not until you have tried it that you find that the block that is moved includes line b, does not include line c, and that the block ends up immediately in front of line a. Most of the functions operate almost instantaneously, but the renumbering takes an appreciable time. Mentor took 2 minutes 10 seconds to renumber the 370 line program I used to test it on. That may not be much slower than most renumber programs, but it's a long wait when it happens after every move, copy and delete. RELIABILITY I could not find any bugs in Mentor, it gives an error message if you type in invalid commands such as trying to move nonexistent lines, it also gives error messages if renumbering would give a line number greater than 9999 or if there is not enough memory left to carry out a block copy operation. VERDICT The documentation describes Mentor as a 'toolkit', but it is really an editing package. You could reasonably expect a toolkit to include debugging aids as well as the editing functions, but the only debugging aid in Mentor is the variable dump and this does not display the variables in a suitable form to help you debug a Basic program. The editing functions are useful, but you have to specify a block of lines by giving the numbers of the first line in the block and the line following the last line of the block. And that certainly doesn't make for ease of use.