Pointers and references: Difference between revisions
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There are not other possible operations on Fortran "pointers" (at least before Fortran 2003).
=={{header|FreeBASIC}}==
<lang freebasic>' FB 1.05.0 Win64
Type Cat
name As String
age As Integer
End Type
Type CatInfoType As Sub (As Cat Ptr)
Sub printCatInfo(c As Cat Ptr)
Print "Name "; c->name, "Age"; c-> age
Print
End Sub
' create Cat object on heap and store a pointer to it
Dim c As Cat Ptr = New Cat
' set fields using the pointer and the "crow's foot" operator
c->name = "Fluffy"
c->age = 9
' print them out through a procedure pointer
Dim cit As CatInfoType = ProcPtr(printCatInfo)
cit(c)
Delete c
c = 0
Dim i As Integer = 3
' create an integer pointer variable and set it to the address of 'i'
Dim pi As Integer Ptr = @i
'change the variable through the pointer
*pi = 4
'print out the result
print "i ="; *pi
'create a reference to the variable i
Dim ByRef As Integer j = i
' set j (and hence i) to a new value
j = 5
' print them out
Print "i ="; i, "j ="; j
Sleep</lang>
{{out}}
<pre>
Name Fluffy Age 9
i = 4
i = 5 j = 5
</pre>
=={{header|Go}}==
Go has pointers but no pointer arithmetic. In general it disallows many operations that are common in other languages but have proven to be common sources of programming errors.
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