csh scripting question

[CTho9305]

What is the case where this works:

if ("x$x" == "xyes') then
...
endif

but this just produces a syntax error?

if ($x == "yes") then
...
endif

I know I've run into the second one breaking before, when x is blank or a newline or something like that... but I can't reproduce it. The cases where I ran into it were in a complex maze of nested csh scripts; I haven't had much luck creating a small example to show the danger of the second form.

 

[VinDSL]

[...]this just produces a syntax error?

What did the error say?

I do a lot of coding. The wording of the error message will give you the best clue...

 

[VinDSL]

if ("x$x" == "xyes') then

Did you type that correctly?

That single quote (at the end) doesn't look right...

If that was NOT a typo, I'd try:

if ("$x" == "yes') then

Thinking about it a little (assuming your first example works - but it's a typo here) I would try:

if ("$x" == "yes") then

If $x is a string, you might need to wrap it in single quotes. For instance:

if ('$x' == "yes") then

Or, you might even try (more conventional coding):

if ($x == yes) then

Kinda hard to tell without looking at the whole script.

 

[CTho9305]

Yes, the single quote is a typo. I don't remember the exact error, and if I could reproduce it I wouldn't need to ask the question 🙂

I think the error was the same as what this produces:
if ( == "yes") then

 

[VinDSL]

I don't remember the exact error, and if I could reproduce it I wouldn't need to ask the question 🙂

Chasing phantom logic errors is great sport, but...

If you cannot reproduce the error, it's a moot question, yes?

Is the script working now?!?!?

 

[CTho9305]

I prefer to understand why my code works - I prefer to avoid cargo cult programming. So, no, I don't see it as moot.