change string into an integer

[Michiel Spape]

Hi David,
Point taken... This auto-casting is the black art, I tell you! After programming e-prime experiments for a while, I find the VB type of programming makes one extremely careless and lazy, and it seems all other coding skills degenerate because of it...
Cheers,
Mich

Michiel Spapé
Research Fellow
Perception & Action group
University of Nottingham
School of Psychology


-----Original Message-----
From: e-prime at googlegroups.com [mailto:e-prime at googlegroups.com] On Behalf Of David McFarlane
Sent: 23 August 2010 19:51
To: e-prime at googlegroups.com; e-prime at googlegroups.com
Subject: RE: change string into an integer

Michiel Spape wrote:
>2. Attributes themselves are like (or just are?) variants, which 
>VisualBasic slightly awkwardly casts depending on their value.

Just on that point, context attributes are not variants, they are 
always just ordinary strings.  But do not take my word for that, if 
you run the following code in any inline,

     c.SetAttrib "MyAttrib", 0
     MsgBox TypeName( c.GetAttrib("MyAttrib") )

the message box will indicate that MyAttrib has the type "String", no 
matter what you put in for the value of the attribute.

That said, Visual Basic (and hence E-Basic) will attempt to cast the 
attribute to an appropriate type as it gets used.  E.g., both

     c.SetAttrib "MyAttrib", 1
     MsgBox 2 + TypeName( c.GetAttrib("MyAttrib") )

and

     c.SetAttrib "MyAttrib", 1
     MsgBox TypeName( c.GetAttrib("MyAttrib") ) + 2

produce the numeric result 3, whereas

     c.SetAttrib "MyAttrib", 1
     MsgBox "2" + TypeName( c.GetAttrib("MyAttrib") )

produces the string "21", and

     c.SetAttrib "MyAttrib", 1
     MsgBox TypeName( c.GetAttrib("MyAttrib") ) + 2

produces the string "12".

So it is a safer practice to always explicitly cast attributes to the 
desired type, e.g.

iValue = CInt( c.GetAttrib("MyAttrib") )

-- dkm

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