Suppress printing methods in a piped script

General Usage
,
1

I am writing a short script in Julia, which is piped in from an encompassing Bash script. I want to suppress printing of “f (generic function with 1 method)” outputs, as in

$ cat <<EOF | julia
> foo() = 1
> EOF
foo (generic function with 1 method)

but I want to keep stdout and stderr as is.

2

Can you terminate each line with ;? I assume this ends up launching the REPL, and passing your input as an actual file instead of through stdin is not an option due to your execution environment.

3

That was the first thing I tried, but it does not help (should have said).

bash-5.2$ cat <<EOF | julia
> foo() = 1;
> EOF
foo (generic function with 1 method)

If necessary I can export to a temporary file but the environment may not support that, so I would prefer not to if there is another solution.

Is there a command line switch for non-interactive mode? The opposite of -i.

4

A workaround is putting the entire script in a let block, as in

cat <<EOF | julia
> let
>     foo(x) = x + 1
>     println(foo(3))
>     nothing
> end
> EOF
4
5

The let block isn’t even necessary, just ending the code with nothing does the trick.

Edit: in fact even that isn’t necessary since println returns nothing already.

Edit2: the nothing (or println) needs to be on the same line as the definition, separated by semicolon.

6

I don’t think that is correct, as the REPL prints line by line. Eg

bash-5.2$ cat <<EOF | julia
> foo() = 1
> nothing
> EOF
foo (generic function with 1 method)
7

See my second edit above

bash-3.2$ cat <<EOF | julia
> foo(x)=x+1
> println(foo(1))
> EOF
foo (generic function with 1 method)
2

vs

bash-3.2$ cat <<EOF | julia
> foo(x)=x+1; nothing
> EOF
bash-3.2$ cat <<EOF | julia
> foo(x)=x+1; println(foo(1))
> EOF
2
8

Just use julia - to treat stdin as a script rather than as interactive inputs. e.g. with your heredoc example:

% cat <<EOF | julia -
foo() = 1
EOF

gives no output. (This is a standard Unix idiom.)

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