A prompt is quite common in MUDs. The prompt display useful details about your character that you are likely to want to keep tabs on at all times, such as health, magical power etc. It might also show things like in-game time, weather and so on. Many modern MUD clients (including Evennia’s own webclient) allows for identifying the prompt and have it appear in a correct location (usually just above the input line). Usually it will remain like that until it is explicitly updated.
Sending a prompt¶
A prompt is sent using the
prompt keyword to the
msg() method on
objects. The prompt will be sent without any line breaks.
self.msg(prompt="HP: 5, MP: 2, SP: 8")
You can combine the sending of normal text with the sending (updating of the prompt):
self.msg("This is a text", prompt="This is a prompt")
You can update the prompt on demand, this is normally done using OOB-tracking of the relevant Attributes (like the character’s health). You could also make sure that attacking commands update the prompt when they cause a change in health, for example.
Here is a simple example of the prompt sent/updated from a command class:
from evennia import Command class CmdDiagnose(Command): """ see how hurt your are Usage: diagnose [target] This will give an estimate of the target's health. Also the target's prompt will be updated. """ key = "diagnose" def func(self): if not self.args: target = self.caller else: target = self.search(self.args) if not target: return # try to get health, mana and stamina hp = target.db.hp mp = target.db.mp sp = target.db.sp if None in (hp, mp, sp): # Attributes not defined self.caller.msg("Not a valid target!") return text = "You diagnose %s as having " \ "%i health, %i mana and %i stamina." \ % (hp, mp, sp) prompt = "%i HP, %i MP, %i SP" % (hp, mp, sp) self.caller.msg(text, prompt=prompt)
A prompt sent with every command¶
The prompt sent as described above uses a standard telnet instruction (the Evennia web client gets a special flag). Most MUD telnet clients will understand and allow users to catch this and keep the prompt in place until it updates. So in principle you’d not need to update the prompt every command.
However, with a varying user base it can be unclear which clients are
used and which skill level the users have. So sending a prompt with
every command is a safe catch-all. You don’t need to manually go in and
edit every command you have though. Instead you edit the base command
class for your custom commands (like
MuxCommand in your
mygame/commands/command.py folder) and overload the
at_post_cmd() hook. This hook is always called after the main
func() method of the Command.
from evennia import default_cmds class MuxCommand(default_cmds.MuxCommand): # ... def at_post_cmd(self): "called after self.func()." caller = self.caller prompt = "%i HP, %i MP, %i SP" % (caller.db.hp, caller.db.mp, caller.db.sp) caller.msg(prompt=prompt)
Modifying default commands¶
If you want to add something small like this to Evennia’s default commands without modifying them directly the easiest way is to just wrap those with a multiple inheritance to your own base class:
# in (for example) mygame/commands/mycommands.py from evennia import default_cmds # our custom MuxCommand with at_post_cmd hook from commands.command import MuxCommand # overloading the look command class CmdLook(default_cmds.CmdLook, MuxCommand): pass
The result of this is that the hooks from your custom
will be mixed into the default
CmdLook through multiple inheritance.
Next you just add this to your default command set:
# in mygame/commands/default_cmdsets.py from evennia import default_cmds from commands import mycommands class CharacterCmdSet(default_cmds.CharacterCmdSet): # ... def at_cmdset_creation(self): # ... self.add(mycommands.CmdLook())
This will automatically replace the default
look command in your
game with your own version.