when_echo_fns, when_exception_fns

Gamma: Version 4.0
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# `when_echo_fns`, `when_exception_fns`

`when_echo_fns`, `when_exception_fns` -- indicate the functions for echos or exceptions on a point.

## Syntax

    when_echo_fns (symbol)
    when_exception_fns (symbol)

## Arguments

`symbol`

  A point name, as a symbol.

## Returns

A list of expressions to be evaluated when an echo or exception occurs on the `symbol`.

## Example

        Gamma> add_echo_function(#temp,#princ("echo\n"));
        (princ "echo\n")
        Gamma> add_echo_function(#temp,#temp/2);
        (/ temp 2)
        Gamma> when_echo_fns(#temp);
        ((/ temp 2) (princ "echo\n") t)
        Gamma> write_point(#temp,22);
        t
        Gamma> next_event();
        echo
    (11 t t)
        Gamma>

## See Also

`add_echo_function, add_exception_function`, `remove_echo_function`, `remove_exception_function`

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