Skip to main content

Code Review: Removing the need for FoxTools

In a recent code compile of a client's application, I noticed some immediate compilation warnings pop up. The application ran fine but the errors were related to functions that exist in the ever popular FOXTOOLS library.

As some background, FoxTools is a FoxPro API library that provide a wide variety of functions (mostly found in the Windows DLL) that, at one point, were not available in FoxPro (going back as far as FoxPro 2.6). Since then, every edition of Visual FoxPro has introduced new functions replacing the need for using Foxtools (to give you an idea about some of the functions that exist in the FOXTOOLS.FLL, check out this post but you can also see it by opening FOXTOOLS.CHM in your VFP Home folder).

Now, when some of the functions were added into VFP, they were added using the same syntax as in the library, thereby requiring no code changes (yeah!). However, others were renamed to be more VFP like.  The one that immediately comes to mind is GETFILEVERSION() and AGETFILEVERSION (the native VFP function).

Most VFP array functions all accept the array as the first parameter (examples: ASCAN(arrayname,search), APRINTERS(arryname), ADIR(arrayname,skeleton). The FoxTools.fll GETFILEVERSION() function passed the array as the second parameter:

DIMENSION la(1)
IF GETFILEVERSION("MyAPP.EXE",@la)>0

ENDIF

The VFP native function is much more standardized:
IF AGETFILEVERSION(la,"MYAPP.EXE")>0

ENDIF

So it's a one character change - (not necessarily trivial if you have a lot of updates to make) - pretty straightforward.

But the code I came across used two of the other FoxTools functions that many developers like to use that have been upgraded in recent versions of FoxPro: WORDS() and WORDNUM().

From FoxTools, WORDS( ) returns the number of words in a particular string and includes a second parameter for the delimiters available. WORDNUM() returns the actual word requested. Example (and yes, note there is no space after the first comma).

lcText = "The name is Bond,James Bond."
? WORDS(lcText)

returns 5. Wait, you say, there are actually 6 words in there. Well, by default, WORDS() only treats spaces and tabs as delimiters so it misses that comma. So let's do:

? WORDS(lcText,CHR(9)+" ,")

With the second parameter, all of the characters that would delimiter a word are passed. This can go one step further with WORDNUM.

? WORDNUM(lcText,4)

returns "Bond,James" whereas:

? WORDNUM(lcText,4,CHR(9)+" ,")

returns simply "Bond"

The VFP functions are similar and perhaps make the code a little more readable (a subjective distinction to be sure). Otherwise, the functions are identical:

? GETWORDCOUNT(lcText) && Returns 4
? GETWORDCOUNT(lcText,CHR(9)+" ,") && Returns 5

? GETWORDNUM(lcText,4,CHR(9)+" ,") && Returns "Bond"

A quick note - the delimiter parameter is simply a list of characters are used. I put the CHR(9) in there so you can see the "tab" instead of the other chars. A great opportunity to use the #DEFINE statement.

#DEFINE _worddelims CHR(9)+" ,"

Changing the WORDS and WORDNUM functions in the code to the VFP internal functions removed the annoying compile time errors (a nit-picky issue to be sure) but also can make the code a little easier to read for VFP developers who may not be familiar with the Foxtools functions.

Why Get Rid of FoxTools?

So is this really necessary? After all, if Foxtools is available - why not use it?

1. Fewer files to distribute and variables to deal with. If you can do it from within VFP, why not? In addition, if you forget to say SET LIBRARY TO - you get errors (ugh!).

2. Performance. OK - this may be squabbling over tenths of seconds - but in my quick test (using War and Peace as the great example), the FoxTools functions were slower than the VFP counterparts. Not by much (less than a tenth of a second) but still there.

(Aside: for a great article on neat tricks with VFP and War and Peace, I point you to Steven Black's  much reprinted article on text)

These functions were added to FoxPro with version 7 - so unless you're still working in VFP 6, there is no good reason - or is there?

Ok, there may be one argument for keeping Foxtools around in the above scenario - variable length.

WORDS and WORDNUM are not as big as GETWORDCOUNT() and GETWORDNUM(). Is that a real reason? I don't think so but you might. 

Do you have any others?

Comments

Unknown said…
There is another reason for changing wordNum to getWordNum and that is wordNum will not retrieve more than 255 characters as 1 one word. getWordNum does not have that limitation.
Turns out this is an important difference when you are reading incoming POST header data in HTTP communications.
Good article thanks.

Popular posts from this blog

Well, that explains CodePlex...

In a move that will be sure to anger open source (or rather anti-paid software, anti-Microsoft open source)  zealots, Microsoft is planning to buy GitHub . A year ago, I mused about why Microsoft would shut down CodePlex and how the world needs competing source code repositories to be strong. I'm not the only one per this Slashdot article  : "...   people have warned about GitHub becoming as large as it did as problematic because it concentrates too much of the power to make or break the open source world in a single entity, moreso because there were valid questions about GitHubs financial viability...." - Jacques Mattheij I will be interested in seeing this play out - whether developers jump ship or not. Have all the efforts Microsoft has made in pushing towards open source be seen as genuine or will all the zealots jump ship or maybe even attack? Microsoft's comment about why they shut down CodePlex referred to how spammers were using CodePlex. Well, GitHub

Attending Southwest Fox 2019 could change your life - Find out how

Southwest Fox is coming up in October and as I do every year, I spoke with the organizers Rick , Doug and Tamar on the FoxShow. Deadlines for Southwest Fox: Super-saver price (before July 1): $695 Early-bird price (before August 1): $770 Regular price (August 1 and later): $820 This year, I took a different approach with separate shows for each organizer but the main message is still the same : July 1st is their Go/No-Go date. Conferences don't talk about this very often. I don't think developers really question if Apple will hold their WWDC in June or Microsoft will hold their Build conference - but that's because those conferences are vendor-led. Southwest Fox is a community-driven conference - it's not driven by a company with an agenda. Listen to the interviews and you can hear how important each of the organizers feel the live connection between speakers and among attendees.

Virtual FoxFest - A New Way to Conference

If you haven't been keeping up with the news around the Fox community, the Southwest Fox conference has gone digital now showing up as  Virtual FoxFest .  At $49, it's a steal and a great way to learn some new ideas and get inspired. While the reasoning for this change is fairly obvious with the year of COVID - for me, this is something that has been a long time coming. I appreciate many people's needs for a physical conference but the world is very large and it's difficult to get people from around the world into a single physical location. I recently attended a single-track conference via YouTube (a Quasar conference). YouTube's Live stream provided a very handy way to watch, rewind and communicate with people online. While Tamar, Doug and Rick are still making decisions related to the streaming platform, there are lots of great options available. I'm really looking forward to it. The FoxPro community has also really felt its international roots