zsh in ksh emulation mode: typeset -i "allows" string as variable value

["Tristan TERPELLE" <tristan.terpelle@xxxxxxxxxxxxxxx>]

We're running zsh in ksh emulation. It has come to our attention that
it's possible to assign a non-integer value to a variable defined as
integer with "typeset -i" (or with "integer"). 

After assigning a string to an integer variable, the exit code is 0. The
new value of the variable is 0 aswell. 

On HP-UX's ksh, however, such an operation isn't permitted resulting in
an error message and an exit code of 1.

Is this normal behaviour for zsh or a bug? Can this behaviour be changed
through zsh' options?


For example, zsh-4.2.6-2.hotfix on RHEL 5.1 x86_64

foo@bar: typeset -i day=5
foo@bar: echo $?
0
foo@bar: echo $day
5
foo@bar: day=five
foo@bar: echo $?
0
foo@bar: echo $day
0
foo@bar: typeset -i day=five
foo@bar: echo $?
0
foo@bar: echo $day
0
foo@bar: uname -a
Linux bar 2.6.18-53.el5 #1 SMP Wed Oct 10 16:34:19 EDT 2007 x86_64
x86_64 x86_64 GNU/Linux
foo@bar: rpm -q zsh
zsh-4.2.6-2.hotfix

... and ksh on HP-UX 11.11

foo@hpux: typeset -i day=5
foo@hpux: echo $?
0
foo@hpux: echo $day
5
foo@hpux: day=five
ksh: five: bad number
foo@hpux: echo $?
1
foo@hpux: echo $day
5
foo@hpux: uname -a
HP-UX hpux B.11.11 U 9000/800 645092970 unlimited-user license


---

Tristan Terpelle
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