how to reassign or increment a variable in erlang

Chandrashekhar Mullaparthi <>
Thu Nov 14 12:08:47 CET 2002


Suresh,

You can do something like this.

-record(myrecord, {a,b}).

mnesia:dirty_write(#myrecord{a=1, b=2}).

[#myrecord{b=BVal}=Rec] = mnesia:dirty_read({myrecord, 1})
mnesia:dirty_write(Rec#myrecord{b=BVal+1}).

If you are specifically looking for counters, look at
mnesia:dirty_update_counter/2

Chandru

-----Original Message-----
From: Suresh S [mailto:]
Sent: 14 November 2002 10:20
To: erlang
Subject: how to reassign or increment a variable in erlang


Hi dear,

even though it is not possible to reassing a variable
in erlang,i need to increment a counter(variable),
and assign it to the same variable,
have any other ideas on this issue 
please let me know

i am really looking out for a solution 
to increment an attrbute value in mnesia table

how it can be done

advanced thanx
suresh s



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