<s>
A	O
source-to-source	B-Language
translator	I-Language
,	O
source-to-source	B-Language
compiler	I-Language
(	O
S2S	B-Language
compiler	I-Language
)	O
,	O
transcompiler	B-Language
,	O
or	O
transpiler	B-Language
is	O
a	O
type	O
of	O
translator	B-Application
that	O
takes	O
the	O
source	O
code	O
of	O
a	O
program	O
written	O
in	O
a	O
programming	O
language	O
as	O
its	O
input	O
and	O
produces	O
an	O
equivalent	O
source	O
code	O
in	O
the	O
same	O
or	O
a	O
different	O
programming	O
language	O
.	O
</s>
<s>
A	O
source-to-source	B-Language
translator	I-Language
converts	O
between	O
programming	O
languages	O
that	O
operate	O
at	O
approximately	O
the	O
same	O
level	O
of	O
abstraction	B-Application
,	O
while	O
a	O
traditional	O
compiler	B-Language
translates	O
from	O
a	O
higher	B-Language
level	I-Language
programming	I-Language
language	I-Language
to	O
a	O
lower	B-Language
level	I-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
For	O
example	O
,	O
a	O
source-to-source	B-Language
translator	I-Language
may	O
perform	O
a	O
translation	O
of	O
a	O
program	O
from	O
Python	B-Language
to	O
JavaScript	B-Language
,	O
while	O
a	O
traditional	O
compiler	B-Language
translates	O
from	O
a	O
language	O
like	O
C	B-Language
to	O
assembler	B-Language
or	O
Java	B-Language
to	O
bytecode	B-Language
.	O
</s>
<s>
An	O
automatic	O
parallelizing	O
compiler	B-Language
will	O
frequently	O
take	O
in	O
a	O
high	B-Language
level	I-Language
language	I-Language
program	O
as	O
an	O
input	O
and	O
then	O
transform	O
the	O
code	O
and	O
annotate	O
it	O
with	O
parallel	B-Operating_System
code	I-Operating_System
annotations	O
(	O
e.g.	O
,	O
OpenMP	B-Application
)	O
or	O
language	O
constructs	O
(	O
e.g.	O
</s>
<s>
Fortran	B-Application
's	O
forall	O
statements	O
)	O
.	O
</s>
<s>
Another	O
purpose	O
of	O
source-to-source-compiling	O
is	O
translating	O
legacy	O
code	O
to	O
use	O
the	O
next	O
version	O
of	O
the	O
underlying	O
programming	O
language	O
or	O
an	O
API	B-Application
that	O
breaks	O
backward	B-General_Concept
compatibility	I-General_Concept
.	O
</s>
<s>
It	O
will	O
perform	O
automatic	O
code	O
refactoring	O
which	O
is	O
useful	O
when	O
the	O
programs	O
to	O
refactor	O
are	O
outside	O
the	O
control	O
of	O
the	O
original	O
implementer	O
(	O
for	O
example	O
,	O
converting	O
programs	O
from	O
Python	B-Language
2	O
to	O
Python	B-Language
3	O
,	O
or	O
converting	O
programs	O
from	O
an	O
old	O
API	B-Application
to	O
the	O
new	O
API	B-Application
)	O
or	O
when	O
the	O
size	O
of	O
the	O
program	O
makes	O
it	O
impractical	O
or	O
time-consuming	O
to	O
refactor	O
it	O
by	O
hand	O
.	O
</s>
<s>
Transcompilers	B-Language
may	O
either	O
keep	O
translated	O
code	O
structure	O
as	O
close	O
to	O
the	O
source	O
code	O
as	O
possible	O
to	O
ease	O
development	O
and	O
debugging	O
of	O
the	O
original	O
source	O
code	O
or	O
may	O
change	O
the	O
structure	O
of	O
the	O
original	O
code	O
so	O
much	O
that	O
the	O
translated	O
code	O
does	O
not	O
look	O
like	O
the	O
source	O
code	O
.	O
</s>
<s>
There	O
are	O
also	O
debugging	O
utilities	O
that	O
map	O
the	O
transcompiled	B-Language
source	O
code	O
back	O
to	O
the	O
original	O
code	O
;	O
for	O
example	O
,	O
the	O
JavaScript	B-Language
Source	I-Language
Map	I-Language
standard	O
allows	O
mapping	O
of	O
the	O
JavaScript	B-Language
code	O
executed	O
by	O
a	O
web	B-Application
browser	I-Application
back	O
to	O
the	O
original	O
source	O
when	O
the	O
JavaScript	B-Language
code	O
was	O
,	O
for	O
example	O
,	O
minified	O
or	O
produced	O
by	O
a	O
transcompiled-to-JavaScript	O
language	O
.	O
</s>
<s>
Examples	O
include	O
Closure	B-Language
Compiler	I-Language
,	O
CoffeeScript	B-Application
,	O
Dart	B-Language
,	O
Haxe	B-Language
,	O
Opal	O
,	O
TypeScript	B-Language
and	O
Emscripten	B-Language
.	O
</s>
<s>
So	O
called	O
Assembly	B-Language
language	I-Language
translators	B-Application
are	O
a	O
class	O
of	O
source-to-source	O
translators	B-Application
converting	O
code	O
from	O
one	O
assembly	B-Language
language	I-Language
into	O
another	O
,	O
including	O
(	O
but	O
not	O
limited	O
to	O
)	O
across	O
different	O
processor	O
families	O
and	O
system	B-Device
platforms	I-Device
.	O
</s>
<s>
Intel	O
marketed	O
their	O
16-bit	O
processor	O
8086	B-General_Concept
to	O
be	O
source	B-General_Concept
compatible	I-General_Concept
to	O
the	O
8080	B-General_Concept
,	O
an	O
8-bit	O
processor	O
.	O
</s>
<s>
To	O
support	O
this	O
,	O
Intel	O
had	O
an	O
ISIS-II-based	O
translator	B-Application
from	O
8080	B-General_Concept
to	O
8086	B-General_Concept
source	O
code	O
named	O
CONV86	O
(	O
also	O
referred	O
to	O
as	O
CONV-86	O
and	O
CONVERT86	O
)	O
available	O
to	O
OEM	O
customers	O
since	O
1978	O
,	O
possibly	O
the	O
earliest	O
program	O
of	O
this	O
kind	O
.	O
</s>
<s>
It	O
supported	O
multiple	O
levels	O
of	O
translation	O
and	O
ran	O
at	O
2MHz	O
on	O
an	O
Intel	O
Microprocessor	O
Development	O
System	O
MDS-800	O
with	O
8-inch	B-Device
floppy	I-Device
drives	O
.	O
</s>
<s>
Seattle	O
Computer	O
Products	O
 '	O
(	O
SCP	O
)	O
offered	O
TRANS86.COM	O
,	O
written	O
by	O
Tim	O
Paterson	O
in	O
1980	O
while	O
developing	O
86-DOS	B-Operating_System
.	O
</s>
<s>
The	O
utility	O
could	O
translate	O
Intel	B-General_Concept
8080	I-General_Concept
and	O
Zilog	B-General_Concept
Z80	I-General_Concept
assembly	O
source	O
code	O
(	O
with	O
Zilog/Mostek	O
mnemonics	O
)	O
into	O
source	O
code	O
for	O
the	O
Intel	B-General_Concept
8086	I-General_Concept
(	O
in	O
a	O
format	O
only	O
compatible	O
with	O
SCP	O
's	O
cross-assembler	O
ASM86	O
for	O
CP/M	B-Application
-80	I-Application
)	O
,	O
but	O
supported	O
only	O
a	O
subset	O
of	O
opcodes	B-Language
,	O
registers	O
and	O
modes	O
,	O
and	O
often	O
still	O
required	O
significant	O
manual	O
correction	O
and	O
rework	O
afterwards	O
.	O
</s>
<s>
Also	O
,	O
performing	O
only	O
a	O
mere	O
transliteration	O
,	O
the	O
brute-force	O
single-pass	B-Language
translator	B-Application
did	O
not	O
carry	O
out	O
any	O
register	O
and	O
jump	O
optimizations	O
.	O
</s>
<s>
The	O
SCP	O
version	O
1	O
of	O
TRANS86.COM	O
ran	O
on	O
Z80-based	O
systems	O
.	O
</s>
<s>
Once	O
86-DOS	B-Operating_System
was	O
running	O
,	O
Paterson	O
,	O
in	O
a	O
self-hosting-inspired	O
approach	O
,	O
utilized	O
TRANS86	O
to	O
convert	O
itself	O
into	O
a	O
program	O
running	O
under	O
86-DOS	B-Operating_System
.	O
</s>
<s>
Later	O
in	O
1982	O
,	O
the	O
translator	B-Application
was	O
apparently	O
also	O
available	O
from	O
Microsoft	O
.	O
</s>
<s>
Also	O
named	O
TRANS86	O
,	O
Sorcim	O
offered	O
an	O
8080	B-General_Concept
to	O
8086	B-General_Concept
translator	B-Application
as	O
well	O
since	O
December	O
1980	O
.	O
</s>
<s>
Like	O
SCP	O
's	O
program	O
it	O
was	O
designed	O
to	O
port	O
CP/M	B-Application
-80	I-Application
application	O
code	O
(	O
in	O
ASM	O
,	O
MAC	O
,	O
RMAC	O
or	O
ACT80	O
assembly	O
format	O
)	O
to	O
MS-DOS	B-Device
(	O
in	O
a	O
format	O
compatible	O
with	O
ACT86	O
)	O
.	O
</s>
<s>
In	O
ACT80	O
format	O
it	O
also	O
supported	O
a	O
few	O
Z80	B-General_Concept
mnemonics	O
.	O
</s>
<s>
The	O
program	O
ran	O
under	O
CP/M	B-Application
-80	I-Application
,	O
MP/M	B-Operating_System
-80	I-Operating_System
and	O
Cromemco	B-Operating_System
DOS	I-Operating_System
with	O
a	O
minimum	O
of	O
24KB	O
of	O
RAM	O
,	O
and	O
had	O
no	O
restrictions	O
on	O
the	O
source	O
file	O
size	O
.	O
</s>
<s>
Much	O
more	O
sophisticated	O
and	O
the	O
first	O
to	O
introduce	O
optimizing	B-Application
compiler	I-Application
technologies	O
into	O
the	O
source	O
translation	O
process	O
was	O
Digital	O
Research	O
's	O
XLT861.0	O
in	O
September	O
1981	O
.	O
</s>
<s>
The	O
program	O
was	O
written	O
by	O
Gary	O
Kildall	O
and	O
translated	O
source	O
code	O
for	O
the	O
Intel	B-General_Concept
8080	I-General_Concept
processor	O
(	O
in	O
a	O
format	O
compatible	O
with	O
ASM	O
,	O
MAC	O
or	O
RMAC	O
assemblers	B-Language
)	O
into	O
source	O
code	O
for	O
the	O
8086	B-General_Concept
(	O
compatible	O
with	O
ASM86	O
)	O
.	O
</s>
<s>
Using	O
global	O
data	O
flow	O
analysis	O
on	O
8080	B-General_Concept
register	O
usage	O
,	O
the	O
five-phase	O
multi-pass	B-Application
translator	B-Application
would	O
also	O
optimize	O
the	O
output	O
for	O
code	O
size	O
and	O
take	O
care	O
of	O
calling	O
conventions	O
(	O
CP/M	B-Application
-80	I-Application
BDOS	B-Operating_System
calls	O
were	O
mapped	O
into	O
BDOS	B-Operating_System
calls	O
for	O
CP/M	B-Operating_System
-86	I-Operating_System
)	O
,	O
so	O
that	O
CP/M	B-Application
-80	I-Application
and	O
MP/M	B-Operating_System
-80	I-Operating_System
programs	O
could	O
be	O
ported	O
to	O
the	O
CP/M	B-Operating_System
-86	I-Operating_System
and	O
MP/M	B-Operating_System
-86	I-Operating_System
platforms	B-Device
automatically	O
.	O
</s>
<s>
XLT86.COM	O
itself	O
was	O
written	O
in	O
PL/I	O
-80	O
for	O
CP/M	B-Application
-80	I-Application
platforms	B-Device
.	O
</s>
<s>
Alternatively	O
,	O
XLT86	O
was	O
also	O
available	O
for	O
DEC	O
VAX/VMS	O
.	O
</s>
<s>
Although	O
XLT86	O
's	O
input	O
and	O
output	O
worked	O
on	O
source-code	O
level	O
,	O
the	O
translator	B-Application
's	O
in-memory	O
representation	O
of	O
the	O
program	O
and	O
the	O
applied	O
code	O
optimizing	O
technologies	O
set	O
the	O
foundation	O
to	O
binary	B-Application
recompilation	I-Application
.	O
</s>
<s>
2500ADSoftware	O
offered	O
an	O
8080	B-General_Concept
to	O
8086	B-General_Concept
source-code	B-Language
translator	I-Language
as	O
part	O
of	O
their	O
XASM	O
suite	O
for	O
CP/M	B-Application
-80	I-Application
machines	O
with	O
Z80	B-General_Concept
as	I-General_Concept
well	O
as	O
for	O
Zilog	O
ZEUS	O
and	O
Olivetti	O
PCOS	O
systems	O
.	O
</s>
<s>
Since	O
1979	O
,	O
Zilog	O
offered	O
a	O
Z80	B-General_Concept
to	O
Z8000	B-Device
translator	B-Application
as	O
part	O
of	O
their	O
PDS8000	O
development	O
system	O
.	O
</s>
<s>
Advanced	O
Micro	O
Computers	O
(	O
AMC	O
)	O
and	O
2500ADSoftware	O
offered	O
Z80	B-General_Concept
to	O
Z8000	B-Device
translators	B-Application
as	O
well	O
.	O
</s>
<s>
The	O
latter	O
was	O
named	O
TRANS	O
and	O
was	O
available	O
for	O
Z80	B-General_Concept
CP/M	B-Application
,	O
CP/M	B-Operating_System
-86	I-Operating_System
,	O
MS-DOS	B-Device
and	O
PCOS	O
.	O
</s>
<s>
The	O
Z88DK	O
development	O
kit	O
provides	O
a	O
Z80	B-General_Concept
to	O
i486	B-General_Concept
source	B-Language
code	I-Language
translator	I-Language
targeting	O
nasm	B-Application
named	O
"	O
to86.awk	O
"	O
,	O
written	O
in	O
2008	O
by	O
Stefano	O
Bodrato	O
.	O
</s>
<s>
It	O
is	O
in	O
turn	O
based	O
on	O
an	O
8080	B-General_Concept
to	O
Z80	B-General_Concept
converter	O
written	O
in	O
2003	O
by	O
Douglas	O
Beattie	O
,	O
Jr.	O
,	O
named	O
"	O
toz80.awk	O
"	O
.	O
</s>
<s>
In	O
2021	O
,	O
Brian	O
Callahan	O
wrote	O
an	O
8080	B-General_Concept
CP/M	B-Application
2.2	O
to	O
MS-DOS	B-Device
source	B-Language
code	I-Language
translator	I-Language
targeting	O
nasm	B-Application
named	O
8088ify	O
.	O
</s>
<s>
The	O
first	O
implementations	O
of	O
some	O
programming	O
languages	O
started	O
as	O
transcompilers	B-Language
,	O
and	O
the	O
default	O
implementation	O
for	O
some	O
of	O
those	O
languages	O
are	O
still	O
transcompilers	B-Language
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
table	O
below	O
,	O
a	O
CoffeeScript	B-Application
maintainer	O
provides	O
a	O
list	O
of	O
languages	O
that	O
compile	B-Language
to	O
JavaScript	B-Language
.	O
</s>
<s>
When	O
developers	O
want	O
to	O
switch	O
to	O
a	O
different	O
language	O
while	O
retaining	O
most	O
of	O
an	O
existing	O
codebase	O
,	O
it	O
might	O
be	O
better	O
to	O
use	O
a	O
transcompiler	B-Language
compared	O
to	O
rewriting	O
the	O
whole	O
software	O
by	O
hand	O
.	O
</s>
<s>
Depending	O
on	O
the	O
quality	O
of	O
the	O
transcompiler	B-Language
,	O
the	O
code	O
may	O
or	O
may	O
not	O
need	O
manual	O
intervention	O
in	O
order	O
to	O
work	O
properly	O
.	O
</s>
<s>
This	O
is	O
different	O
from	O
"	O
transcompiled	B-Language
languages	O
"	O
where	O
the	O
specifications	O
demand	O
that	O
the	O
output	O
source	O
code	O
always	O
works	O
without	O
modification	O
.	O
</s>
<s>
All	O
transcompilers	B-Language
used	O
to	O
port	O
a	O
codebase	O
will	O
expect	O
manual	O
adjustment	O
of	O
the	O
output	O
source	O
code	O
if	O
there	O
is	O
a	O
need	O
to	O
achieve	O
maximum	O
code	O
quality	O
in	O
terms	O
of	O
readability	O
and	O
platform	O
convention	O
.	O
</s>
<s>
Tool	O
Source	O
language	O
Target	B-Application
language	I-Application
Comments	O
2to3	O
script	O
Python	B-Language
2	O
Python	B-Language
3	O
Even	O
though	O
2to3	O
does	O
its	O
best	O
at	O
automating	O
the	O
translation	O
process	O
,	O
further	O
manual	O
corrections	O
are	O
often	O
needed	O
.	O
</s>
<s>
Emscripten	B-Language
LLVM	B-Application
bytecode	B-Language
JavaScript	B-Language
This	O
allows	O
running	O
C/C	O
++	O
codebases	O
in	O
a	O
browser	B-Application
for	O
example	O
c2go	O
C	B-Language
Go	B-Application
Before	O
the	O
1.5	O
release	O
,	O
the	O
Go	B-Application
compiler	B-Language
was	O
written	O
in	O
C	B-Language
.	O
An	O
automatic	B-Application
translator	I-Application
was	O
developed	O
to	O
automatically	O
convert	O
the	O
compiler	B-Language
codebase	O
from	O
C	B-Language
into	O
Go	B-Application
.	O
</s>
<s>
Since	O
Go	B-Application
1.5	O
,	O
the	O
"	O
compiler	B-Language
and	O
runtime	B-Library
are	O
now	O
implemented	O
in	O
Go	B-Application
and	O
assembler	B-Language
,	O
without	O
C	B-Language
"	O
.	O
</s>
<s>
C2Rust	O
C	B-Language
Rust	B-Application
C2Rust	O
takes	O
C	B-Language
code	O
as	O
input	O
and	O
outputs	O
unsafe	O
Rust	B-Application
code	O
,	O
focusing	O
on	O
preserving	O
compatibility	O
with	O
the	O
original	O
codebase	O
.	O
</s>
<s>
Converting	O
the	O
resulting	O
code	O
to	O
safe	O
and	O
idiomatic	O
Rust	B-Application
code	O
is	O
a	O
manual	O
effort	O
post	O
translation	O
,	O
although	O
an	O
automated	O
tool	O
exists	O
to	O
ease	O
this	O
task	O
.	O
</s>
<s>
Google	B-Language
Web	I-Language
Toolkit	I-Language
Java	B-Language
program	O
that	O
uses	O
a	O
specific	O
API	B-Application
JavaScript	B-Language
The	O
Java	B-Language
code	I-Language
is	O
a	O
little	O
bit	O
constrained	O
compared	O
to	O
normal	O
Java	B-Language
code	I-Language
.	O
</s>
<s>
Js_of_ocaml	O
of	O
Ocsigen	O
OCaml	B-Language
JavaScript	B-Language
J2Eif	O
Java	B-Language
Eiffel	B-Language
The	O
resulting	O
Eiffel	B-Language
code	O
has	O
classes	O
and	O
structures	O
similar	O
to	O
the	O
Java	B-Language
program	O
but	O
following	O
Eiffel	B-Language
syntax	O
and	O
conventions	O
.	O
</s>
<s>
C2Eif	O
C	B-Language
Eiffel	B-Language
The	O
resulting	O
Eiffel	B-Language
code	O
has	O
classes	O
and	O
structures	O
that	O
try	O
to	O
be	O
as	O
clean	O
as	O
possible	O
.	O
</s>
<s>
The	O
tool	O
is	O
complete	O
and	O
relies	O
on	O
embedding	O
the	O
C	B-Language
and	O
assembly	B-Language
code	I-Language
if	O
it	O
cannot	O
translate	O
it	O
properly	O
.	O
</s>
<s>
Swiftify	O
Objective-C	B-Language
Swift	B-Application
Swiftify	O
is	O
an	O
online	O
source	B-Language
to	I-Language
source	I-Language
conversion	I-Language
tool	O
from	O
Objective-C	B-Language
into	O
Swift	B-Application
.	O
</s>
<s>
It	O
assists	O
developers	O
who	O
are	O
migrating	O
all	O
or	O
part	O
of	O
their	O
iOS	O
codebase	O
into	O
Swift	B-Application
.	O
</s>
<s>
The	O
conversion	O
is	O
aimed	O
primarily	O
at	O
converting	O
the	O
syntax	O
between	O
Objective-C	B-Language
and	O
Swift	B-Application
,	O
and	O
is	O
helped	O
because	O
Apple	O
took	O
efforts	O
to	O
ensure	O
compatibility	O
between	O
Swift	B-Application
and	O
Objective-C	B-Language
runtimes	B-Library
.	O
</s>
<s>
Runtime	B-Library
Converter	O
PHP	B-Application
Java	B-Language
The	O
Runtime	B-Library
Converter	O
is	O
an	O
automatic	O
tool	O
which	O
converts	O
PHP	B-Application
source	O
code	O
into	O
Java	B-Language
source	I-Language
code	I-Language
.	O
</s>
<s>
There	O
is	O
a	O
Java	B-Language
runtime	B-Library
library	O
for	O
certain	O
features	O
of	O
the	O
PHP	B-Application
language	I-Application
,	O
as	O
well	O
as	O
the	O
ability	O
to	O
call	O
into	O
the	O
PHP	B-Application
binary	O
itself	O
using	O
JNI	O
for	O
PHP	B-Application
standard	O
library	O
and	O
extension	O
function	O
calls	O
.	O
</s>
<s>
A	O
transcompiler	B-Language
pipeline	O
is	O
what	O
results	O
from	O
recursive	O
transcompiling	B-Language
.	O
</s>
<s>
By	O
stringing	O
together	O
multiple	O
layers	O
of	O
tech	O
,	O
with	O
a	O
transcompile	B-Language
step	O
between	O
each	O
layer	O
,	O
technology	O
can	O
be	O
repeatedly	O
transformed	O
,	O
effectively	O
creating	O
a	O
distributed	O
language	B-Language
independent	I-Language
specification	I-Language
.	O
</s>
<s>
XSLT	B-Application
is	O
a	O
general-purpose	O
transform	O
tool	O
that	O
can	O
be	O
used	O
between	O
many	O
different	O
technologies	O
,	O
to	O
create	O
such	O
a	O
derivative	B-General_Concept
code	I-General_Concept
pipeline	O
.	O
</s>
<s>
Recursive	O
transcompilation	B-Language
(	O
or	O
recursive	O
transpiling	B-Language
)	O
is	O
the	O
process	O
of	O
applying	O
the	O
notion	O
of	O
transcompiling	B-Language
recursively	O
,	O
to	O
create	O
a	O
pipeline	O
of	O
transformations	O
(	O
often	O
starting	O
from	O
a	O
single	B-Application
source	I-Application
of	I-Application
truth	I-Application
)	O
which	O
repeatedly	O
turn	O
one	O
technology	O
into	O
another	O
.	O
</s>
<s>
By	O
repeating	O
this	O
process	O
,	O
one	O
can	O
turn	O
A	O
→	O
B	O
→	O
C	B-Language
→	O
D	O
→	O
E	O
→	O
F	O
and	O
then	O
back	O
into	O
.	O
</s>
<s>
In	O
each	O
of	O
the	O
different	O
versions	O
that	O
the	O
transcompiler	B-Language
pipeline	O
produces	O
,	O
that	O
information	O
is	O
preserved	O
.	O
</s>
<s>
It	O
might	O
take	O
on	O
many	O
different	O
shapes	O
and	O
sizes	O
,	O
but	O
by	O
the	O
time	O
it	O
comes	O
back	O
to	O
,	O
having	O
been	O
transcompiled	B-Language
six	O
times	O
in	O
the	O
pipeline	O
above	O
,	O
the	O
information	O
returns	O
to	O
its	O
original	O
state	O
.	O
</s>
<s>
This	O
information	O
which	O
survives	O
the	O
transform	O
through	O
each	O
format	O
,	O
from	O
,	O
is	O
(	O
by	O
definition	O
)	O
derivative	O
content	O
or	O
derivative	B-General_Concept
code	I-General_Concept
.	O
</s>
<s>
Recursive	O
transcompilation	B-Language
takes	O
advantage	O
of	O
the	O
fact	O
that	O
transcompilers	B-Language
may	O
either	O
keep	O
translated	O
code	O
as	O
close	O
to	O
the	O
source	O
code	O
as	O
possible	O
to	O
ease	O
development	O
and	O
debugging	O
of	O
the	O
original	O
source	O
code	O
,	O
or	O
else	O
they	O
may	O
change	O
the	O
structure	O
of	O
the	O
original	O
code	O
so	O
much	O
,	O
that	O
the	O
translated	O
code	O
does	O
not	O
look	O
like	O
the	O
source	O
code	O
.	O
</s>
<s>
There	O
are	O
also	O
debugging	O
utilities	O
that	O
map	O
the	O
transcompiled	B-Language
source	O
code	O
back	O
to	O
the	O
original	O
code	O
;	O
for	O
example	O
,	O
JavaScript	B-Language
source	I-Language
maps	I-Language
allow	O
mapping	O
of	O
the	O
JavaScript	B-Language
code	O
executed	O
by	O
a	O
web	B-Application
browser	I-Application
back	O
to	O
the	O
original	O
source	O
in	O
a	O
transcompiled-to-JavaScript	O
language	O
.	O
</s>
