How do I make an optional parameter in a slash command (Pycord)

Question

I have a slash command in my Pycord bot. Here is the code:

@bot.slash_command(name='greet', description='Greet someone!')
async def greet(ctx, name):
    await ctx.send('Hello ' + name + '!')

How would I make "name" an optional parameter? I tried setting name=None, but it doesn't work.

Answer 1

There are a couple of ways to do this. The first way is the easiest and laziest way which is just setting the parameter to a default value as such:

@bot.slash_command(name='greet', description='Greet someone!')
async def greet(ctx, name=''):
    await ctx.respond(f'Hello {name}!')

The second way that I know of is from the example code in the Pycord repository:

from discord.commands import Option

@bot.slash_command(name='greet', description='Greet someone!')
async def greet(ctx, name: Option(str, "Enter your friend's name", required = False, default = '')):
    await ctx.respond(f'Hello {name}!')

EDIT:

await ctx.send(f'Hello {name}!') was changed to await ctx.respond(f'Hello {name}!') because discord requires a response from a slash command otherwise discord will show an ugly error message saying that there was no response.

UPDATE:

As of June 2022, you can write your slash commands with the default parameter value expressed in the decorator:

@bot.slash_command(name='greet', description='Greet someone!')
@option(
    "name", 
    description="Enter your friend's name",
    required=False,
    default=''
)
async def greet(
    ctx: discord.ApplicationContext,
    name: str
):
    await ctx.respond(f"Hello {name}!")