First argument should convert to a variable and execute

Techno Teerth

6/12/23, 5:31 AM

I have declared arg="echo demo"

When we execute the command my_command arg, then arg should be converted to $arg and should be executed like

my_command () {
    $arg
}

How do I call $1 as a variable?

0 + 0

bash

Liso

6/12/23, 6:02 AM

Isn't what you have declared `arg="echo demo"` is a variable ?

tripleee

6/12/23, 12:32 PM

There is no way for your function to work correctly with quoted strings. Assigning a command to a string is probably the wrong thing to want to do anyway. Probably see https://mywiki.wooledge.org/BashFAQ/050

Score:2

Ubuntu

zwets

6/12/23, 7:49 AM

The eval shell built-in does what you want:

$ help eval
eval: eval [arg ...]
    Execute arguments as a shell command.

    Combine ARGs into a single string, use the result as input to the shell,
    and execute the resulting commands.

So your function could look like this:

my_command() {
    eval $1
}

Instead of $1 you could also put $* and my_command will take an arbitrary number of arguments.

Note that by then my_command is little less than an alias for eval, so you could as well do:

alias my_command=eval

0 + 0

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: First argument should convert to a variable and execute

TH: First argument should convert to a variable and execute

RO: First argument should convert to a variable and execute

RU: First argument should convert to a variable and execute

VI: First argument should convert to a variable and execute

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