Creating a function over multiple lines

35 Lines

f=
0[
c=
'\
c\
o\
n\
s\
t\
r\
u\
c\
t\
o\
r'
][
c]
`
r\
e\
t\
u\
r\
n\
'\
b\
a\
r\
b\
a\
r\
i\
a\
n'
`

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Uses the fact that 0 is a number, the constructor of 0 is Number, and the constructor of Number is Function.

32 Lines

0[
c=
'\
c\
o\
n\
s\
t\
r\
u\
c\
t\
o\
r'
][
c]
`
f=
_\
=>
'\
b\
a\
r\
b\
a\
r\
i\
a\
n'
`(
)

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This essentially runs

Function(`
f=
_=>
'barbarian'`)()

which uses the IIFE structure. Added bonus is that we can line-break some parts in the function body to reduce the line count.

24 Lines

f=
''
[
'\
t\
r\
i\
m'
][
'\
b\
i\
n\
d'
]`
b\
a\
r\
b\
a\
r\
i\
a\
n`

Try it online!

Inline version:

f=''['trim']['bind']`
barbarian`

Since all we want is to return a string, we can get away with a string method bound to a string. By using trim, we can also safely leave a beginning newline.

Here is a 38 line solution:

f=
[]
[
'\
m\
a\
p'
][
'\
c\
o\
n\
s\
t\
r\
u\
c\
t\
o\
r'
]`
r\
e\
t\
u\
r\
n\
'\
b\
a\
r\
b\
a\
r\
i\
a\
n\
'`

It creates a function using the Function constructor, which it accesses from [].map.constructor using subscript notation ([]['map']['constructor']). This is the method JSFuck uses to create functions.