When and when not to use hash # symbol in ColdFusion?

cfml, coldfusion

Solution

There is no inconsistency (or very little: none of what you cite are inconsistencies), it's just you not understanding the rules (which are pretty basic really). It's all in the docs: "Using number signs"

In short, within a CFML statement, all elements are considered CFML, so there is no need to specifically mark them as such. EG:

<cfset myVar = someFunction(anArgument)>

There is no ambiguity there that `myVar`, `someFunction` and `anArgument` are anything other than CFML constructs, so no need to do this sort of thing:

<cfset myVar = #someFunction(anArgument)#>

As some people are inclined to do.

In the middle of text or within a string, there is ambiguity as to what's text and what's CFML, so one needs to use pound signs to mark them as such. EG:

<cfset myVar = "The time is #now()#">

It's necessary to us pound-signs there to disambiguate `now()` as being a CFML statement, an not just part of the string, eg:

<cfset myVar = "CFML has a function now() which returns the current timestamp">

Equally:

<cfquery>
    SELECT col1
    FROM table2
    WHERE col2 = #someValue#
</cfquery>

There would be no way of knowing `someValue` is a variable there without marking it as such.

That's basically it. It's not complicated.

Problem

I use the `#` symbol around every dynamic value in my application and after posting some of my code on here for help, I've been told there's no need to use the `#` in many places e.g. `<cfif>` statements. So I have started removing the # symbols, until I realised I broke my application because I removed the # symbols from the `value=""` attribute of a `<cfprocparam>` tag. I am confused as to: - Why use the `#` symbol is some places and not others (and what is the benefit of not using it?) - Why if they are not required in `<cfif>` and `<cfargument>` tags are they suddenly required in `<cfprocparam>` tags? - Due to this lack of consistency, is it not better to just wrap hashes around every dynamic value in the first place?

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