Use of Name Installer attribute with a variable

I'm a newbie, a little bit confused with the usage of variables with the Name Installer attribute.

Below is the code. Also a bit confused if the usage of variable with the Math plugin is the right and recommended way.

Please let me know what I might be doing wrong. Thank you.

-Jramak

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Var floatWeight

!define WEIGHT_INCREMENT 3

; Item weight read from file.py is 2
!searchparse /file "C:\file.py" `__text__ = \
int("$Itemweight:`ITEM_WEIGHT `$"[11:-2])`

Section "Pre-processing Operations" SEC01
Math::Script "$floatWeight = ${WEIGHT_INCREMENT} + ${ITEM_WEIGHT} / 100.00"
SectionEnd
;Name to be assigned "Weight 3.02"
Name "Weight ${floatWeight}"
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OK, so I figured this out. Posting the answer so it can help others.

In general, it is a bit confusing to as whether to use '{}' for variables or omit them or use '()'.
------------------------------------------------------------

Var floatWeight
!define WEIGHT_INCREMENT 3

; Item weight read from file.py is 2
!searchparse /file "C:\file.py" `__text__ = \
int("$Itemweight:`ITEM_WEIGHT `$"[11:-2])`

Function .onInit
Math::Script "r1 = ${WEIGHT_INCREMENT} + ${ITEM_WEIGHT} / 100.00"
StrCpy $floatWeight $1
FunctionEnd

;Name to be assigned "Weight 3.02"
Name "Weight $floatWeight"
------------------------------------------------------------

How confusing can it be?

${define}
$(langstring)
$var

(defines are set at compile time, the others at runtime)