rust-lang
Fold support for code blocks
Problem
For large code blocks, there's no option to fold them. For example, something similar to GitHub makrdown's <details> feature.
Proposed Solution
To make, for example, strace output optionally expandable, I could do below in GitHub markdown:
strace output
$ strace cat filename
execve("/usr/bin/cat", ["cat", "filename"], 0x7ffe36b26958 /* 62 vars */) = 0
brk(NULL) = 0x5651e8f08000
arch_prctl(0x3001 /* ARCH_??? */, 0x7ffd8d760bf0) = -1 EINVAL (Invalid argument)
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f390c25a000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=73663, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 73663, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f390c248000
close(3) = 0
openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\320v\2\0\0\0\0\0"..., 832) = 832
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=2224288, ...}, AT_EMPTY_PATH) = 0
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
mmap(NULL, 1953104, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f390c06b000
mmap(0x7f390c091000, 1400832, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x26000) = 0x7f390c091000
mmap(0x7f390c1e7000, 339968, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x17c000) = 0x7f390c1e7000
mmap(0x7f390c23a000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1ce000) = 0x7f390c23a000
mmap(0x7f390c240000, 32080, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f390c240000
close(3) = 0
mmap(NULL, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f390c068000
arch_prctl(ARCH_SET_FS, 0x7f390c068740) = 0
set_tid_address(0x7f390c068a10) = 23150
set_robust_list(0x7f390c068a20, 24) = 0
rseq(0x7f390c069060, 0x20, 0, 0x53053053) = 0
mprotect(0x7f390c23a000, 16384, PROT_READ) = 0
mprotect(0x5651e7e56000, 4096, PROT_READ) = 0
mprotect(0x7f390c28f000, 8192, PROT_READ) = 0
prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
munmap(0x7f390c248000, 73663) = 0
getrandom("\x2a\xcf\xe3\x91\x15\x16\xe5\x39", 8, GRND_NONBLOCK) = 8
brk(NULL) = 0x5651e8f08000
brk(0x5651e8f29000) = 0x5651e8f29000
openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=224104272, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 224104272, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f38fea00000
close(3) = 0
newfstatat(1, "", {st_mode=S_IFCHR|0620, st_rdev=makedev(0x88, 0), ...}, AT_EMPTY_PATH) = 0
openat(AT_FDCWD, "filename", O_RDONLY) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=13, ...}, AT_EMPTY_PATH) = 0
fadvise64(3, 0, 0, POSIX_FADV_SEQUENTIAL) = 0
mmap(NULL, 139264, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f390c046000
read(3, "hello, world\n", 131072) = 13
write(1, "hello, world\n", 13hello, world
) = 13
read(3, "", 131072) = 0
munmap(0x7f390c046000, 139264) = 0
close(3) = 0
close(1) = 0
close(2) = 0
exit_group(0) = ?
+++ exited with 0 +++
Having something like this in mdBook will be greatly helpful.
Notes
I noticed hiding code lines but:
- it's usable only for rust code, at the moment
- it requires adding
#in front of every line you don't want to show, and that could become painful if there are many lines
I tried to find a similar issue in the repo, but could only find issues for foldable Table of Contents.
Turns out this already exists as can be seen on the kubebuilder book. I couldn't find it in the mdbook docs, however. Maybe it's called something that I don't know of.
Turns out this already exists as can be seen on the kubebuilder book. I couldn't find it in the mdbook docs, however. Maybe it's called something that I don't know of.
They seem to use <details> as HTML directly!
