#!/usr/bin/perl

$name = "tom";
# reading through a piped-in file
while (<>) {
  if (/$name/) {
    print $_;
  }
}

# -----

if ("larry, moe, and curly" =~ /\W+(moe)\W+/) {
  print "$`\n";
  print "$&\n";  # NB: not the same as $1
  print "$'\n";
}

# -----

$_ = "larry, moe, and curly";
s/curly/shemp/;
print "$_\n";  # prints "larry, moe, and shemp"

$_ = "larry, moe, and curly";
s/(\w+)\W+(\w+)/$2 $1/;  # swaps words
print "$_\n";

$_ = "larry, moe, and curly had curly hair";
s/curly/shemp/g;
print "$_\n";

$_ = "Larry, Moe, and Curly";
s/(\w+)/\U$1/;   # makes first word uppercase
print "$_\n";
s/(\w+)/\L$1/g;  # makes all words lowercase
print "$_\n";

# -----