Fern playground
Edit a Fern program and hit
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(
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) to see its output.
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Run (wasm)
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View assembly
arm64
arm64-darwin
x86-64
Build component
wasi:cli/run
wasi:http/incoming-handler
— pick an example —
hello, world
factorial
string methods
sort_i32_asc
union types + match
Result error handling
lex+parse arithmetic
format(fmt, args)
http handler
loading runtime…
🌙
request
GET
POST
PUT
DELETE
PATCH
headers
(one
Name: value
per line)
body
source
Output
Assembly
arm64
arm64-darwin
x86-64
output
problems
assembly