> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/perl6-rosettacode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/perl6-rosettacode/programming_tasks/s/string_prepend.md).

# String prepend

```perl
# explicit concatentation
$_ = 'byte';
$_ = 'kilo' ~ $_;
.say;

# interpolation as concatenation
$_ = 'buck';
$_ = "mega$_";
.say;

# lvalue substr
$_ = 'bit';
substr-rw($_,0,0) = 'nano';
.say;

# regex substitution
$_ = 'fortnight';
s[^] = 'micro';
.say;

# reversed append assignment
$_ = 'cooper'; 
$_ [R~]= 'mini';
.say;
```

#### Output:

```
kilobyte
megabuck
nanobit
microfortnight
minicooper
```