Another syntax question

[Ed Jay]

I have two functions, one of which is called from within the other, which
is called from an HTML page. The called function is passed parameters that
I'd like to pass to the argument calling the second function:

HTML: onClick routine1(a,b,c);

js:

function routine1(a,b,c) {routine2(a,b); do something with a,b,c;}

The parameters a and b are not parsed by routine2(a,b). What am I doing
wrong?
--
Ed Jay (remove 'M' to respond by email)

[RobG]

Ed Jay said on 22/04/2006 8:32 AM AEST:

I have two functions, one of which is called from within the other, which
is called from an HTML page. The called function is passed parameters that
I'd like to pass to the argument calling the second function:

HTML: onClick routine1(a,b,c);

js:

function routine1(a,b,c) {routine2(a,b); do something with a,b,c;}

The parameters a and b are not parsed by routine2(a,b).
I think you mean *passed* to routine2 and not passed back to routine1.
Or maybe not...

If you really mean parsed, what are their values and what should
routine2() be doing with them?

What am I doing wrong?

Not explaining your problem and not providing a simple example. ;-)

Your snippet, as posted, should be fine. But I suspect that you are
passing a and b to routines2(), doing something with them, then
expecting them to be modified in routine1() but you either aren't return
the modified values, or aren't assigning them to a and b in routine1().

From here on, I'll call them r1() and r2() to save typing.

In javascript, a function can only return a single reference. If you
want to return a number of values, you have to put them inside an object
(say an Array) and return a reference to that:

r2(a, b){
// do something with a and b
return [a, b];
}

r1(a, b, c){
var returnedArray = r2(a, b);
a = returnedArray[0];
b = returnedArray[1];
}
Note that in r2() I could have called the variables anything I like
because just the values are passed to and fro. Even if you are passing
objects, you can still call them whatever you like because references
are passed, not the actual object.
Alternatively, you can design routine2() so that it has access to
variables inside routine1():

<script type="text/javascript">

function r1(a, b, c)
{
// Declare r2 inside r1
function r2(){

// r2 has access to local variables of r1()
alert('In r2, a=' + a + ', b=' + b);

// and can modify them
a = 'freddy';
b = 'suzie';
}

// Call r2
r2();

// Show changed variable values
alert('After r2, a=' + a + ', b=' + b);
}

// Call r1
r1('fred', 'sue', 'harry');

</script>
Note that r2() has access to, and can modify, the values of variables in
r1(), also that only r1() can call r2(), it is a private method.

You can make r2() available outside r1() if you want, read Douglas
Crockford's article here:

<URL:http://javascript.crockford.com/private.html>
There is a lot of other good stuff on his site too.
--
Rob
Group FAQ: <URL:http://www.jibbering.com/FAQ>

[Ed Jay]

RobG scribed:

Ed Jay said on 22/04/2006 8:32 AM AEST:

I have two functions, one of which is called from within the other, which
is called from an HTML page. The called function is passed parameters that
I'd like to pass to the argument calling the second function:

HTML: onClick routine1(a,b,c);

js:

function routine1(a,b,c) {routine2(a,b); do something with a,b,c;}

The parameters a and b are not parsed by routine2(a,b).
I think you mean *passed* to routine2 and not passed back to routine1.
Or maybe not...

If you really mean parsed, what are their values and what should
routine2() be doing with them?

What am I doing wrong?

Not explaining your problem and not providing a simple example. ;-)

Your snippet, as posted, should be fine. But I suspect that you are
passing a and b to routines2(), doing something with them, then
expecting them to be modified in routine1() but you either aren't return
the modified values, or aren't assigning them to a and b in routine1().

From here on, I'll call them r1() and r2() to save typing.

In javascript, a function can only return a single reference. If you
want to return a number of values, you have to put them inside an object
(say an Array) and return a reference to that:

r2(a, b){
// do something with a and b
return [a, b];
}

I'm not returning values to r1().
r1(a, b, c){
var returnedArray = r2(a, b);
a = returnedArray[0];
b = returnedArray[1];
}
Note that in r2() I could have called the variables anything I like
because just the values are passed to and fro. Even if you are passing
objects, you can still call them whatever you like because references
are passed, not the actual object.
Alternatively, you can design routine2() so that it has access to
variables inside routine1():

<script type="text/javascript">

function r1(a, b, c)
{
// Declare r2 inside r1
function r2(){
I don't want to declare the 2nd function within the first. I want to call
r2(a,b) from within r1(a,b,c) using a subset of the parameters passed to
r1(a,b,c).

In my situation, r2(a,b) is a lengthy and often-used subroutine. In most
cases, its use is independent of r1().
// r2 has access to local variables of r1()
alert('In r2, a=' + a + ', b=' + b);

// and can modify them
a = 'freddy';
b = 'suzie';
}

// Call r2
r2();

// Show changed variable values
alert('After r2, a=' + a + ', b=' + b);
}

// Call r1
r1('fred', 'sue', 'harry');

</script>
Note that r2() has access to, and can modify, the values of variables in
r1(), also that only r1() can call r2(), it is a private method.

You can make r2() available outside r1() if you want, read Douglas
Crockford's article here:

<URL:http://javascript.crockford.com/private.html>
There is a lot of other good stuff on his site too.

Thanks, RobG, for the detailed response. I apologize for not stating my
issue clearly. It isn't nearly as complex as you understood it to be.
Regardless, I must have had a syntax error someplace. I rewrote the
function and it works.

Real world example:

function tester1(a,b,c) {alert("f1("+a+b+c+")"); tester2(a,b);}

function tester2(a,b) {alert("f2("+a+b+")");}

Thanks again for your help.
--
Ed Jay (remove 'M' to respond by email)