<s>
Miranda	B-Language
is	O
a	O
lazy	O
,	O
purely	B-Language
functional	I-Language
programming	O
language	O
designed	O
by	O
David	O
Turner	O
as	O
a	O
successor	O
to	O
his	O
earlier	O
programming	O
languages	O
SASL	B-Language
and	O
KRC	B-Language
,	O
using	O
some	O
concepts	O
from	O
ML	B-Language
and	O
Hope	B-Language
.	O
</s>
<s>
It	O
was	O
produced	O
by	O
Research	O
Software	O
Ltd	O
.	O
of	O
England	O
(	O
which	O
holds	O
a	O
trademark	O
on	O
the	O
name	O
Miranda	B-Language
)	O
and	O
was	O
the	O
first	O
purely	B-Language
functional	I-Language
language	O
to	O
be	O
commercially	O
supported	O
.	O
</s>
<s>
Miranda	B-Language
was	O
first	O
released	O
in	O
1985	O
as	O
a	O
fast	O
interpreter	O
in	O
C	B-Language
for	O
Unix-flavour	O
operating	O
systems	O
,	O
with	O
subsequent	O
releases	O
in	O
1987	O
and	O
1989	O
.	O
</s>
<s>
It	O
had	O
a	O
strong	O
influence	O
on	O
the	O
later	O
Haskell	B-Language
language	I-Language
.	O
</s>
<s>
In	O
2020	O
a	O
version	O
of	O
Miranda	B-Language
was	O
released	O
as	O
open	O
source	O
under	O
a	O
BSD	O
licence	O
.	O
</s>
<s>
The	O
codebase	O
has	O
been	O
updated	O
to	O
conform	O
to	O
modern	O
C	B-Language
standards	O
(	O
C11/C18	O
)	O
and	O
to	O
generate	O
64-bit	O
binaries	O
.	O
</s>
<s>
This	O
has	O
been	O
tested	O
on	O
operating	O
systems	O
including	O
Debian	O
,	O
Ubuntu	B-Operating_System
,	O
WSL/Ubuntu	O
,	O
and	O
macOS	B-Application
(	O
Catalina	B-Device
)	O
.	O
</s>
<s>
Miranda	B-Language
is	O
a	O
lazy	O
,	O
purely	B-Language
functional	I-Language
programming	O
language	O
.	O
</s>
<s>
That	O
is	O
,	O
it	O
lacks	O
side	O
effects	O
and	O
imperative	B-Application
programming	I-Application
features	O
.	O
</s>
<s>
A	O
Miranda	B-Language
program	O
(	O
called	O
a	O
script	O
)	O
is	O
a	O
set	O
of	O
equations	O
that	O
define	O
various	O
mathematical	O
functions	O
and	O
algebraic	O
data	O
types	O
.	O
</s>
<s>
Since	O
the	O
parsing	B-Language
algorithm	O
makes	O
intelligent	O
use	O
of	O
layout	B-Language
(	O
indentation	O
,	O
via	O
off-side	B-Language
rule	I-Language
)	O
,	O
bracketing	O
statements	O
are	O
rarely	O
needed	O
and	O
statement	O
terminators	O
are	O
unneeded	O
.	O
</s>
<s>
This	O
feature	O
,	O
inspired	O
by	O
ISWIM	B-Language
,	O
is	O
also	O
used	O
in	O
occam	B-Language
and	O
Haskell	B-Language
and	O
was	O
later	O
popularized	O
by	O
Python	B-Language
.	O
</s>
<s>
An	O
alternative	O
commenting	O
convention	O
affects	O
an	O
entire	O
source	O
code	O
file	O
,	O
known	O
as	O
a	O
"	O
literate	B-Application
script	I-Application
"	O
,	O
in	O
which	O
every	O
line	O
is	O
considered	O
a	O
comment	O
unless	O
it	O
starts	O
with	O
a	O
>	O
sign	O
.	O
</s>
<s>
Miranda	B-Language
's	O
basic	O
data	O
types	O
are	O
char	O
,	O
num	O
and	O
bool	O
.	O
</s>
<s>
A	O
character	O
string	O
is	O
simply	O
a	O
list	O
of	O
char	O
,	O
while	O
num	O
is	O
silently	O
converted	O
between	O
two	O
underlying	O
forms	O
:	O
arbitrary-precision	B-Algorithm
integers	O
(	O
a.k.a.	O
</s>
<s>
bignums	B-Algorithm
)	O
by	O
default	O
,	O
and	O
regular	O
floating	B-Algorithm
point	I-Algorithm
values	I-Algorithm
as	O
required	O
.	O
</s>
<s>
Tuples	B-Application
are	O
sequences	O
of	O
elements	O
of	O
potentially	O
mixed	O
types	O
,	O
analogous	O
to	O
records	O
in	O
Pascal-like	O
languages	O
,	O
and	O
are	O
written	O
delimited	O
with	O
parentheses	O
:	O
</s>
<s>
The	O
list	O
instead	O
is	O
the	O
most	O
commonly	O
used	O
data	O
structure	O
in	O
Miranda	B-Language
.	O
</s>
<s>
More	O
general	O
and	O
powerful	O
list-building	O
facilities	O
are	O
provided	O
by	O
"	O
list	B-Language
comprehensions	I-Language
"	O
(	O
previously	O
known	O
as	O
"	O
ZF	B-Language
expressions	I-Language
"	O
)	O
,	O
which	O
come	O
in	O
two	O
main	O
forms	O
:	O
an	O
expression	O
applied	O
to	O
a	O
series	O
of	O
terms	O
,	O
e.g.	O
</s>
<s>
As	O
these	O
two	O
examples	O
imply	O
,	O
Miranda	B-Language
allows	O
for	O
lists	O
with	O
an	O
infinite	O
number	O
of	O
elements	O
,	O
of	O
which	O
the	O
simplest	O
is	O
the	O
list	O
of	O
all	O
positive	O
integers	O
:	O
1	O
..	O
</s>
<s>
In	O
Miranda	B-Language
,	O
as	O
in	O
most	O
other	O
purely	B-Language
functional	I-Language
languages	O
,	O
functions	O
are	O
first-class	B-Application
citizens	O
,	O
which	O
is	O
to	O
say	O
that	O
they	O
can	O
be	O
passed	O
as	O
arguments	O
to	O
other	O
functions	O
,	O
returned	O
as	O
results	O
,	O
or	O
included	O
as	O
elements	O
of	O
data	O
structures	O
.	O
</s>
<s>
What	O
is	O
more	O
,	O
a	O
function	O
with	O
two	O
or	O
more	O
parameters	O
may	O
be	O
"	O
partially	O
parameterised	O
"	O
,	O
or	O
curried	B-Application
,	O
by	O
supplying	O
fewer	O
arguments	O
than	O
the	O
full	O
number	O
of	O
parameters	O
.	O
</s>
<s>
Although	O
Miranda	B-Language
is	O
a	O
strongly	O
typed	O
programming	O
language	O
,	O
it	O
does	O
not	O
insist	O
on	O
explicit	O
type	O
declarations	O
.	O
</s>
<s>
Finally	O
,	O
it	O
has	O
mechanisms	O
for	O
creating	O
and	O
managing	O
program	O
modules	B-Architecture
whose	O
internal	O
functions	O
are	O
invisible	O
to	O
programs	O
calling	O
those	O
modules	B-Architecture
.	O
</s>
