unshift is like push just from the lower side, kind of inverted shift

a little perldebugger demo 

  DB<9> x @a =(5)
0  5
  DB<10> unshift  @a,4

  DB<11> x @a
0  4
1  5
  DB<12> unshift  @a,1,2,3

  DB<13> x @a
0  1
1  2
2  3
3  4
4  5
  DB<14> push @a, 6

  DB<15> x @a
0  1
1  2
2  3
3  4
4  5
5  6
  DB<16> p shift @a
1
  DB<17> x @a
0  2
1  3
2  4
3  5
4  6
  DB<18> p pop @a
6
  DB<19> x @a
0  2
1  3
2  4
3  5
  DB<20>

[download]

I recommend trying perl -de0 to play around by yourself

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re: I am confused by a "Learning Perl" sample showing "unshift" by LanX
in thread I am confused by a "Learning Perl" sample showing "unshift" by KenAndrews

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