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'''#give''' and '''#take''' are [[ZZT-OOP]] commands for adding and subtracting to counters.
'''#give''' and '''#take''' are [[ZZT-OOP]] commands for adding and subtracting to counters.


The syntax for the commands is:
== Available counters ==


<code>#give <counter> <amount> [<command>]</code>
The following counters can be modified with '''#give''' and '''#take''':
<code>#take <counter> <amount> [<command>]</code>
 
* health
* ammo
* gems
* torches (''ZZT'' only)
* score
* time
* z (''Super ZZT'' only)


The following counters can be modified with '''#give''' and '''#take''':
== Syntax ==


* Health
* <code>#give <counter> <amount> [<command>]</code>
* Ammo
* <code>#take <counter> <amount> [<command>]</code>
* Gems
* Torches (''ZZT'' only)
* Score
* Time
* Z (''Super ZZT'' only)


If the '''#give''' or '''#take''' would result in the counter having a value less than 0 or greater than 32767, then the result of the operation is not stored, and the command is executed instead (if present). The command can be any ZZT-OOP command, but is usually the name of a [[Label|label]] to jump to, as in the following example:
If the '''#give''' or '''#take''' would result in the counter having a value less than 0 or greater than 32767, then the result of the operation is not stored, and the command is executed instead (if present). The command can be any ZZT-OOP command, but is usually the name of a [[Label|label]] to jump to, as in the following example:
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The command argument is rarely used with '''#give''', though it is available to use if necessary.
The command argument is rarely used with '''#give''', though it is available to use if necessary.


==Bugs and Quirks==
== Bugs and Quirks ==
 
[TODO: Verify and explain these]


*The time counter is weird.
* The time counter actually stores the number of seconds ''elapsed'', not the number of seconds ''remaining''; as such, one has to '''#give''' time in order to reduce the amount of time remaining.
*Visual glitches can occur when taking sufficiently large values.
* The command argument does not need to be prefixed with an '''#'''; for example, '''#take gems 10 put s red key''' is as valid as '''#take gems 10 #put s red key'''.
* ZZT displays sidebar numbers by adding a certain number of spaces to the value in question (two for ammo, one for other values). As such, a '''#take''' which reduces the value by a very large amount will cause a visual glitch. For example, '''#take health 95''' on '''Health: 100''' will display '''Health: 5 0''', while the true value of player health is equal to 5.
** To work around this issue, one should '''#take''' values in smaller quantities.
* Counters in ZZT are signed 16-bit values, as is the parsed integer; overflows and underflows outside the range '''-32768'''..'''32767''' are not checked for.
** The Turbo Pascal standard library function for parsing integers from strings, however, operates in 32 bits; this may cause different classes of bugs on 32-bit overflow. (TODO: what bugs?)


{{ZZT-OOP navbox}}
{{ZZT-OOP navbox}}

Latest revision as of 17:12, 29 September 2022

#give and #take are ZZT-OOP commands for adding and subtracting to counters.

Available counters

The following counters can be modified with #give and #take:

  • health
  • ammo
  • gems
  • torches (ZZT only)
  • score
  • time
  • z (Super ZZT only)

Syntax

  • #give <counter> <amount> [<command>]
  • #take <counter> <amount> [<command>]

If the #give or #take would result in the counter having a value less than 0 or greater than 32767, then the result of the operation is not stored, and the command is executed instead (if present). The command can be any ZZT-OOP command, but is usually the name of a label to jump to, as in the following example:

@GemsForHealth
#end
:touch
#take gems 10 tooPoor
#give health 50
#end
:tooPoor
You're to poor to buy health!

The command argument is rarely used with #give, though it is available to use if necessary.

Bugs and Quirks

  • The time counter actually stores the number of seconds elapsed, not the number of seconds remaining; as such, one has to #give time in order to reduce the amount of time remaining.
  • The command argument does not need to be prefixed with an #; for example, #take gems 10 put s red key is as valid as #take gems 10 #put s red key.
  • ZZT displays sidebar numbers by adding a certain number of spaces to the value in question (two for ammo, one for other values). As such, a #take which reduces the value by a very large amount will cause a visual glitch. For example, #take health 95 on Health: 100 will display Health: 5 0, while the true value of player health is equal to 5.
    • To work around this issue, one should #take values in smaller quantities.
  • Counters in ZZT are signed 16-bit values, as is the parsed integer; overflows and underflows outside the range -32768..32767 are not checked for.
    • The Turbo Pascal standard library function for parsing integers from strings, however, operates in 32 bits; this may cause different classes of bugs on 32-bit overflow. (TODO: what bugs?)