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-rw-r--r--users/Profpatsch/blog/default.nix373
-rw-r--r--users/Profpatsch/blog/notes/preventing-oom.md33
-rw-r--r--users/Profpatsch/blog/notes/rust-string-conversions.md53
-rw-r--r--users/Profpatsch/blog/posts/2017-05-04-ligature-emulation-in-emacs.md123
4 files changed, 582 insertions, 0 deletions
diff --git a/users/Profpatsch/blog/default.nix b/users/Profpatsch/blog/default.nix
new file mode 100644
index 000000000000..6ac3c3eb5104
--- /dev/null
+++ b/users/Profpatsch/blog/default.nix
@@ -0,0 +1,373 @@
+{ depot, pkgs, lib, ... }:
+
+let
+  bins = depot.nix.getBins pkgs.lowdown [ "lowdown" ]
+      // depot.nix.getBins pkgs.cdb [ "cdbget" "cdbmake" "cdbdump" ]
+      // depot.nix.getBins pkgs.coreutils [ "mv" "cat" "printf" "test" ]
+      // depot.nix.getBins pkgs.s6-networking [ "s6-tcpserver" ]
+      // depot.nix.getBins pkgs.time [ "time" ]
+      ;
+
+  # /
+  # TODO: use
+  toplevel = [
+    {
+      route = [ "notes" ];
+      name = "Notes";
+      page = {cssFile}: router cssFile;
+    }
+    {
+      route = [ "projects" ];
+      name = "Projects";
+      # page = projects;
+    }
+  ];
+
+  # /notes/*
+  notes = [
+    {
+      route = [ "notes" "preventing-oom" ];
+      name = "Preventing out-of-memory (OOM) errors on Linux";
+      page = {cssFile}: markdownToHtml {
+        name = "preventing-oom";
+        markdown = ./notes/preventing-oom.md;
+        inherit cssFile;
+      };
+    }
+    {
+      route = [ "notes" "rust-string-conversions" ];
+      name = "Converting between different String types in Rust";
+      page = {cssFile}: markdownToHtml {
+        name = "rust-string-conversions";
+        markdown = ./notes/rust-string-conversions.md;
+        inherit cssFile;
+      };
+    }
+  ];
+
+  projects = [
+    {
+      name = "lorri";
+      description = "<code>nix-shell</code> replacement for projects";
+      link = "https://github.com/nix-community/lorri";
+    }
+    {
+      name = "netencode";
+      description = ''A human-readble nested data exchange format inspired by <a href="https://en.wikipedia.org/wiki/Netstring">netstrings</a> and <a href="https://en.wikipedia.org/wiki/Bencode">bencode</a>.'';
+      link = depotCgitLink { relativePath = "users/Profpatsch/netencode/README.md"; };
+    }
+    {
+      name = "yarn2nix";
+      description = ''nix dependency generator for the <a href="https://yarnpkg.com/"><code>yarn</code> Javascript package manager</a>'';
+      link = "https://github.com/Profpatsch/yarn2nix";
+    }
+  ];
+
+  posts = [
+    {
+      date = "2017-05-04";
+      title = "Ligature Emulation in Emacs";
+      subtitle = "It’s not pretty, but the results are";
+      description = "How to set up ligatures using <code>prettify-symbols-mode</code> and the Hasklig/FiraCode fonts.";
+      page = {cssFile}: markdownToHtml {
+        name = "2017-05-04-ligature-emluation-in-emacs";
+        markdown = ./posts/2017-05-04-ligature-emulation-in-emacs.md;
+        inherit cssFile;
+      };
+      route = [ "posts" "2017-05-04-ligature-emluation-in-emacs" ];
+      tags = ["emacs"];
+    }
+  ];
+
+  # convert a markdown file to html via lowdown
+  markdownToHtml = {
+    name,
+    # the file to convert
+    markdown,
+    # css file to add to the final result, as { route }
+    cssFile
+  }:
+    depot.nix.runExecline "${name}.html" {} ([
+      "importas" "out" "out"
+      (depot.users.Profpatsch.lib.debugExec "")
+      bins.lowdown
+        "-s" "-Thtml"
+      ] ++
+        (lib.optional (cssFile != null) (["-M" "css=${mkRoute cssFile.route}"]))
+      ++ [
+        "-o" "$out"
+        markdown
+    ]);
+
+  # takes a { route … } attrset and converts the route lists to an absolute path
+  fullRoute = attrs: lib.pipe attrs [
+    (map (x@{route, ...}: x // { route = mkRoute route; }))
+  ];
+
+  # a cdb from route to a netencoded version of data for each route
+  router = cssFile: lib.pipe (notes ++ posts) [
+    (map (r: with depot.users.Profpatsch.lens;
+      lib.pipe r [
+        (over (field "route") mkRoute)
+        (over (field "page") (_ { inherit cssFile; }))
+      ]))
+    (map (x: {
+      name = x.route;
+      value = depot.users.Profpatsch.netencode.gen.dwim x;
+    }))
+    lib.listToAttrs
+    (cdbMake "router")
+  ];
+
+  # Create a link to the given source file/directory, given the relative path in the depot repo.
+  # Checks that the file exists at evaluation time.
+  depotCgitLink = {
+    # relative path from the depot root (without leading /).
+    relativePath
+  }:
+    assert
+      (lib.assertMsg
+        (builtins.pathExists (depot.path + "/" + relativePath))
+        "depotCgitLink: path /${relativePath} does not exist in depot");
+      "https://code.tvl.fyi/tree/${relativePath}";
+
+  # look up a route by path ($1)
+  router-lookup = cssFile: depot.nix.writeExecline "router-lookup" { readNArgs = 1; } [
+    cdbLookup (router cssFile) "$1"
+  ];
+
+  runExeclineStdout = name: args: cmd: depot.nix.runExecline name args ([
+    "importas" "-ui" "out" "out"
+    "redirfd" "-w" "1" "$out"
+  ] ++ cmd);
+
+  notes-index-html =
+    let o = fullRoute notes;
+    in ''
+      <ul>
+      ${scope o (o: ''
+        <li><a href="${str o.route}">${esc o.name}</a></li>
+      '')}
+      </ul>
+    '';
+
+  notes-index = pkgs.writeText "notes-index.html" notes-index-html;
+
+  # A simple mustache-inspired string interpolation combinator
+  # that takes an object and a template (a function from o to string)
+  # and returns a string.
+  scope = o: tpl:
+    if builtins.typeOf o == "list" then
+      lib.concatMapStringsSep "\n" tpl o
+    else if builtins.typeOf o == "set" then
+      tpl o
+    else throw "${lib.generators.toPretty {} o} not allowed in template";
+
+  # string-escape html (TODO)
+  str = s: s;
+  # html-escape (TODO)
+  esc = s: s;
+  html = s: s;
+
+  projects-index-html =
+  let o = projects;
+  in ''
+    <dl>
+    ${scope o (o: ''
+      <dt><a href="${str o.link}">${esc o.name}</a></dt>
+      <dd>${html o.description}</dd>
+    '')}
+    </dl>
+  '';
+
+  projects-index = pkgs.writeText "projects-index.html" projects-index-html;
+
+  posts-index-html =
+  let o = fullRoute posts;
+  in ''
+    <dl>
+    ${scope o (o: ''
+      <dt>${str o.date} <a href="${str o.route}">${esc o.title}</a></dt>
+      <dd>${html o.description}</dd>
+    '')}
+    </dl>
+  '';
+
+  posts-index = pkgs.writeText "projects-index.html" posts-index-html;
+
+  arglibNetencode = val: depot.nix.writeExecline "arglib-netencode" { } [
+    "export" "ARGLIB_NETENCODE" (depot.users.Profpatsch.netencode.gen.dwim val)
+    "$@"
+  ];
+
+  # A simple http server that serves the site. Yes, it’s horrible.
+  site-server = { cssFile, port }: depot.nix.writeExecline "blog-server" {} [
+    (depot.users.Profpatsch.lib.runInEmptyEnv [ "PATH" ])
+    bins.s6-tcpserver "127.0.0.1" port
+    bins.time "--format=time: %es" "--"
+    runOr return400
+    "pipeline" [
+      (arglibNetencode {
+        what = "request";
+      })
+      depot.users.Profpatsch.read-http
+    ]
+    depot.users.Profpatsch.netencode.record-splice-env
+    runOr return500
+    "importas" "-i" "path" "path"
+    "if" [ depot.tools.eprintf "GET \${path}\n" ]
+    runOr return404
+    "backtick" "-ni" "TEMPLATE_DATA" [
+      # TODO: factor this out of here, this is routing not serving
+      "ifelse" [ bins.test "$path" "=" "/notes" ]
+        [ "export" "content-type" "text/html"
+          "export" "serve-file" notes-index
+          depot.users.Profpatsch.netencode.env-splice-record
+        ]
+      "ifelse" [ bins.test "$path" "=" "/projects" ]
+        [ "export" "content-type" "text/html"
+          "export" "serve-file" projects-index
+          depot.users.Profpatsch.netencode.env-splice-record
+        ]
+      "ifelse" [ bins.test "$path" "=" "/posts" ]
+        [ "export" "content-type" "text/html"
+          "export" "serve-file" posts-index
+          depot.users.Profpatsch.netencode.env-splice-record
+        ]
+      # TODO: ignore potential query arguments. See 404 message
+      "pipeline" [ (router-lookup cssFile) "$path" ]
+      depot.users.Profpatsch.netencode.record-splice-env
+      "importas" "-ui" "page" "page"
+      "export" "content-type" "text/html"
+      "export" "serve-file" "$page"
+      depot.users.Profpatsch.netencode.env-splice-record
+    ]
+    runOr return500
+    "if" [
+      "pipeline" [ bins.printf ''
+        HTTP/1.1 200 OK
+        Content-Type: {{{content-type}}}; charset=UTF-8
+        Connection: close
+
+      '' ]
+      depot.users.Profpatsch.netencode.netencode-mustache
+    ]
+    "pipeline" [ "importas" "t" "TEMPLATE_DATA" bins.printf "%s" "$t" ]
+    depot.users.Profpatsch.netencode.record-splice-env
+    "importas" "-ui" "serve-file" "serve-file"
+    bins.cat "$serve-file"
+  ];
+
+  # run argv or $1 if argv returns a failure status code.
+  runOr = depot.nix.writeExecline "run-or" { readNArgs = 1; } [
+    "foreground" [ "$@" ]
+    "importas" "?" "?"
+    "ifelse" [ bins.test "$?" "-eq" "0" ]
+    []
+    "if" [ depot.tools.eprintf "runOr: exited \${?}, running \${1}\n" ]
+    "$1"
+  ];
+
+  return400 = depot.nix.writeExecline "return400" {} [
+    bins.printf "%s" ''
+      HTTP/1.1 400 Bad Request
+      Content-Type: text/plain; charset=UTF-8
+      Connection: close
+
+    ''
+  ];
+
+  return404 = depot.nix.writeExecline "return404" {} [
+    bins.printf "%s" ''
+      HTTP/1.1 404 Not Found
+      Content-Type: text/plain; charset=UTF-8
+      Connection: close
+
+      This page doesn’t exist! Query arguments are not handled at the moment.
+    ''
+  ];
+
+  return500 = depot.nix.writeExecline "return500" {} [
+    bins.printf "%s" ''
+      HTTP/1.1 500 Internal Server Error
+      Content-Type: text/plain; charset=UTF-8
+      Connection: close
+
+      Encountered an internal server error. Please try again.
+    ''
+  ];
+
+  capture-stdin = depot.nix.writers.rustSimple {
+    name = "capture-stdin";
+    dependencies = [ depot.users.Profpatsch.execline.exec-helpers ];
+  } ''
+    extern crate exec_helpers;
+    use std::io::Read;
+    fn main() {
+      let (args, prog) = exec_helpers::args_for_exec("capture-stdin", 1);
+      let valname = &args[1];
+      let mut v : Vec<u8> = vec![];
+      std::io::stdin().lock().read_to_end(&mut v).unwrap();
+      exec_helpers::exec_into_args("capture-stdin", prog, vec![(valname, v)]);
+    }
+  '';
+
+  # go from a list of path elements to an absolute route string
+  mkRoute = route: "/" + lib.concatMapStringsSep "/" urlencodeAscii route;
+
+  # urlencodes, but only ASCII characters
+  # https://en.wikipedia.org/wiki/Percent-encoding
+  urlencodeAscii = urlPiece:
+    let
+      raw = [ "!" "#" "$" "%" "&" "'" "(" ")" "*" "+" "," "/" ":" ";" "=" "?" "@" "[" "]" ];
+      enc = [ "%21" "%23" "%24" "%25" "%26" "%27" "%28" "%29" "%2A" "%2B" "%2C" "%2F" "%3A" "%3B" "%3D" "%3F" "%40" "%5B" "%5D" ];
+      rest = [ "A" "B" "C" "D" "E" "F" "G" "H" "I" "J" "K" "L" "M" "N" "O" "P" "Q" "R" "S" "T" "U" "V" "W" "X" "Y" "Z" "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r" "s" "t" "u" "v" "w" "x" "y" "z" "0" "1" "2" "3" "4" "5" "6" "7" "8" "9" "-" "_" "." "~" ];
+    in
+    assert lib.assertMsg (lib.all (c: builtins.elem c (raw ++ rest)) (lib.stringToCharacters urlPiece))
+      "urlencodeAscii: the urlPiece must only contain valid url ASCII characters, was: ${urlPiece}";
+    builtins.replaceStrings raw enc urlPiece;
+
+
+  # create a cdb record entry, as required by the cdbmake tool
+  cdbRecord = key: val:
+    "+${toString (builtins.stringLength key)},${toString (builtins.stringLength val)}:"
+    + "${key}->${val}\n";
+
+  # create a full cdbmake input from an attribute set of keys to values (strings)
+  cdbRecords =
+    with depot.nix.yants;
+    defun [ (attrs (either drv string)) string ]
+    (attrs:
+      (lib.concatStrings (lib.mapAttrsToList cdbRecord attrs)) + "\n");
+
+  # run cdbmake on a list of key/value pairs (strings
+  cdbMake = name: attrs: depot.nix.runExecline "${name}.cdb" {
+    stdin = cdbRecords attrs;
+  } [
+    "importas" "out" "out"
+    depot.users.Profpatsch.lib.eprint-stdin
+    "if" [ bins.cdbmake "db" "tmp" ]
+    bins.mv "db" "$out"
+  ];
+
+  # look up a key ($2) in the given cdb ($1)
+  cdbLookup = depot.nix.writeExecline "cdb-lookup" { readNArgs = 2; } [
+    # cdb ($1) on stdin
+    "redirfd" "-r" "0" "$1"
+    # key ($2) lookup
+    bins.cdbget "$2"
+  ];
+
+in depot.nix.readTree.drvTargets {
+   inherit
+    router
+    depotCgitLink
+    site-server
+    notes-index
+    notes-index-html
+    projects-index
+    projects-index-html
+    posts-index-html
+    ;
+
+}
diff --git a/users/Profpatsch/blog/notes/preventing-oom.md b/users/Profpatsch/blog/notes/preventing-oom.md
new file mode 100644
index 000000000000..59ea4f747700
--- /dev/null
+++ b/users/Profpatsch/blog/notes/preventing-oom.md
@@ -0,0 +1,33 @@
+tags: linux
+date: 2020-01-25
+certainty: likely
+status: initial
+title: Preventing out-of-memory (OOM) errors on Linux
+
+# Preventing out-of-memory (OOM) errors on Linux
+
+I’ve been running out of memory more and more often lately. I don’t use any swap space because I am of the opinion that 16GB of memory should be sufficient for most daily and professional tasks. Which is generally true, however sometimes I have a runaway filling my memory. Emacs is very good at doing this for example, prone to filling your RAM when you open json files with very long lines.
+
+In theory, the kernel OOM killer should come in and save the day, but the Linux OOM killer is notorious for being extremely … conservative. It will try to free every internal structure it can before even thinking about touching any userspace processes. At that point, the desktop usually stopped responding minutes ago.
+
+Luckily the kernel provides memory statistics for the whole system, as well as single process, and the [`earlyoom`](https://github.com/rfjakob/earlyoom) tool uses those to keep memory usage under a certain limit. It will start killing processes, “heaviest” first, until the given upper memory limit is satisfied again.
+
+On NixOS, I set:
+
+```nix
+{
+  services.earlyoom = {
+    enable = true;
+    freeMemThreshold = 5; # <%5 free
+  };
+}
+```
+
+and after activation, this simple test shows whether the daemon is working:
+
+```shell
+$ tail /dev/zero
+fish: “tail /dev/zero” terminated by signal SIGTERM (Polite quit request)
+```
+
+`tail /dev/zero` searches for the last line of the file `/dev/zero`, and since it cannot know that there is no next line and no end to the stream of `\0` this file produces, it will fill the RAM as quickly as physically possible. Before it can fill it completely, `earlyoom` recognizes that the limit was breached, singles out the `tail` command as the process using the most amount of memory, and sends it a `SIGTERM`.
diff --git a/users/Profpatsch/blog/notes/rust-string-conversions.md b/users/Profpatsch/blog/notes/rust-string-conversions.md
new file mode 100644
index 000000000000..99071ef9d370
--- /dev/null
+++ b/users/Profpatsch/blog/notes/rust-string-conversions.md
@@ -0,0 +1,53 @@
+# Converting between different String types in Rust
+
+```
+let s: String = ...
+let st: &str = ...
+let u: &[u8] = ...
+let b: [u8; 3] = b"foo"
+let v: Vec<u8> = ...
+let os: OsString = ...
+let ost: OsStr = ...
+
+From       To         Use                                    Comment
+----       --         ---                                    -------
+&str     -> String    String::from(st)
+&str     -> &[u8]     st.as_bytes()
+&str     -> Vec<u8>   st.as_bytes().to_owned()               via &[u8]
+&str     -> &OsStr    OsStr::new(st)
+
+String   -> &str      &s                                     alt. s.as_str()
+String   -> &[u8]     s.as_bytes()
+String   -> Vec<u8>   s.into_bytes()
+String   -> OsString  OsString::from(s)
+
+&[u8]    -> &str      str::from_utf8(u).unwrap()
+&[u8]    -> String    String::from_utf8(u).unwrap()
+&[u8]    -> Vec<u8>   u.to_owned()
+&[u8]    -> &OsStr    OsStr::from_bytes(u)                   use std::os::unix::ffi::OsStrExt;
+
+[u8; 3]  -> &[u8]     &b[..]                                 byte literal
+[u8; 3]  -> &[u8]     "foo".as_bytes()                       alternative via utf8 literal
+
+Vec<u8>  -> &str      str::from_utf8(&v).unwrap()            via &[u8]
+Vec<u8>  -> String    String::from_utf8(v)
+Vec<u8>  -> &[u8]     &v
+Vec<u8>  -> OsString  OsString::from_vec(v)                  use std::os::unix::ffi::OsStringExt;
+
+&OsStr   -> &str      ost.to_str().unwrap()
+&OsStr   -> String    ost.to_os_string().into_string()       via OsString
+                         .unwrap()
+&OsStr   -> Cow<str>  ost.to_string_lossy()                  Unicode replacement characters
+&OsStr   -> OsString  ost.to_os_string()
+&OsStr   -> &[u8]     ost.as_bytes()                         use std::os::unix::ffi::OsStringExt;
+
+OsString -> String    os.into_string().unwrap()              returns original OsString on failure
+OsString -> &str      os.to_str().unwrap()
+OsString -> &OsStr    os.as_os_str()
+OsString -> Vec<u8>   os.into_vec()                          use std::os::unix::ffi::OsStringExt;
+```
+
+
+## Source
+
+Original source is [this document on Pastebin](https://web.archive.org/web/20190710121935/https://pastebin.com/Mhfc6b9i)
diff --git a/users/Profpatsch/blog/posts/2017-05-04-ligature-emulation-in-emacs.md b/users/Profpatsch/blog/posts/2017-05-04-ligature-emulation-in-emacs.md
new file mode 100644
index 000000000000..ba80888badd8
--- /dev/null
+++ b/users/Profpatsch/blog/posts/2017-05-04-ligature-emulation-in-emacs.md
@@ -0,0 +1,123 @@
+title: Ligature Emulation in Emacs
+date: 2017-05-04
+
+Monday was (yet another)
+[NixOS hackathon][hackathon] at [OpenLab Augsburg][ola].
+[Maximilian][mhuber] was there and to my amazement
+he got working ligatures in his Haskell files in Emacs! Ever since Hasklig
+updated its format to use ligatures and private Unicode code points a while ago,
+the hack I had used in my config stopped working.
+
+Encouraged by that I decided to take a look on Tuesday. Long story short, I was
+able to [get it working in a pretty satisfying way][done].
+
+[hackathon]: https://www.meetup.com/Munich-NixOS-Meetup/events/239077247/
+[mhuber]: https://github.com/maximilianhuber
+[ola]: https://openlab-augsburg.de
+[done]: https://github.com/i-tu/Hasklig/issues/84#issuecomment-298803495
+
+What’s left to do is package it into a module and push to melpa.
+
+
+### elisp still sucks, but it’s bearable, sometimes
+
+I’m the kind of person who, when trying to fix something elisp related, normally
+gives up two hours later and three macro calls deep. Yes, homoiconic,
+non-lexically-scoped, self-rewriting code is not exactly my fetish.
+This time the task and the library (`prettify-symbols-mode`) were simple enough
+for that to not happen.
+
+Some interesting technical trivia:
+
+- elisp literal character syntax is `?c`. `?\t` is the tab character
+- You join characters by `(string c1 c2 c3 ...)`
+- [dash.el][dash] is pretty awesome and does what a functional programmer
+  expects. Also, Rainbow Dash.
+- Hasklig and FiraCode multi-column symbols actually [only occupy one column, on
+  the far right of the glyph][glyph]. `my-correct-symbol-bounds` fixes emacs’
+  rendering in that case.
+
+
+[dash]: https://github.com/magnars/dash.el
+[glyph]: https://github.com/tonsky/FiraCode/issues/211#issuecomment-239082368
+
+
+## Appendix A
+
+For reference, here’s the complete code as it stands now. Feel free to paste
+into your config; let’s make it [MIT][mit]. Maybe link to this site, in case there are
+updates.
+
+[mit]: https://opensource.org/licenses/MIT
+
+```elisp
+ (defun my-correct-symbol-bounds (pretty-alist)
+    "Prepend a TAB character to each symbol in this alist,
+this way compose-region called by prettify-symbols-mode
+will use the correct width of the symbols
+instead of the width measured by char-width."
+    (mapcar (lambda (el)
+              (setcdr el (string ?\t (cdr el)))
+              el)
+            pretty-alist))
+
+  (defun my-ligature-list (ligatures codepoint-start)
+    "Create an alist of strings to replace with
+codepoints starting from codepoint-start."
+    (let ((codepoints (-iterate '1+ codepoint-start (length ligatures))))
+      (-zip-pair ligatures codepoints)))
+
+  ; list can be found at https://github.com/i-tu/Hasklig/blob/master/GlyphOrderAndAliasDB#L1588
+  (setq my-hasklig-ligatures
+    (let* ((ligs '("&&" "***" "*>" "\\\\" "||" "|>" "::"
+                   "==" "===" "==>" "=>" "=<<" "!!" ">>"
+                   ">>=" ">>>" ">>-" ">-" "->" "-<" "-<<"
+                   "<*" "<*>" "<|" "<|>" "<$>" "<>" "<-"
+                   "<<" "<<<" "<+>" ".." "..." "++" "+++"
+                   "/=" ":::" ">=>" "->>" "<=>" "<=<" "<->")))
+      (my-correct-symbol-bounds (my-ligature-list ligs #Xe100))))
+
+  ;; nice glyphs for haskell with hasklig
+  (defun my-set-hasklig-ligatures ()
+    "Add hasklig ligatures for use with prettify-symbols-mode."
+    (setq prettify-symbols-alist
+          (append my-hasklig-ligatures prettify-symbols-alist))
+    (prettify-symbols-mode))
+
+  (add-hook 'haskell-mode-hook 'my-set-hasklig-ligatures)
+```
+
+## Appendix B (Update 1): FiraCode integration
+
+I also created a mapping for [FiraCode][fira]. You need to grab the [additional
+symbol font][symbol] that adds (most) ligatures to the unicode private use area.
+Consult your system documentation on how to add it to your font cache.
+Next add `"Fira Code"` and `"Fira Code Symbol"` to your font preferences. Symbol
+only contains the additional characters, so you need both.
+
+If you are on NixOS, the font package should be on the main branch shortly, [I
+added a package][symbol-pkg].
+
+[fira]: https://github.com/tonsky/FiraCode/
+[symbol]: https://github.com/tonsky/FiraCode/issues/211#issuecomment-239058632
+[symbol-pkg]: https://github.com/NixOS/nixpkgs/pull/25517
+
+Here’s the mapping adjusted for FiraCode:
+
+```elisp
+  (setq my-fira-code-ligatures
+    (let* ((ligs '("www" "**" "***" "**/" "*>" "*/" "\\\\" "\\\\\\"
+                  "{-" "[]" "::" ":::" ":=" "!!" "!=" "!==" "-}"
+                  "--" "---" "-->" "->" "->>" "-<" "-<<" "-~"
+                  "#{" "#[" "##" "###" "####" "#(" "#?" "#_" "#_("
+                  ".-" ".=" ".." "..<" "..." "?=" "??" ";;" "/*"
+                  "/**" "/=" "/==" "/>" "//" "///" "&&" "||" "||="
+                  "|=" "|>" "^=" "$>" "++" "+++" "+>" "=:=" "=="
+                  "===" "==>" "=>" "=>>" "<=" "=<<" "=/=" ">-" ">="
+                  ">=>" ">>" ">>-" ">>=" ">>>" "<*" "<*>" "<|" "<|>"
+                  "<$" "<$>" "<!--" "<-" "<--" "<->" "<+" "<+>" "<="
+                  "<==" "<=>" "<=<" "<>" "<<" "<<-" "<<=" "<<<" "<~"
+                  "<~~" "</" "</>" "~@" "~-" "~=" "~>" "~~" "~~>" "%%"
+                  "x" ":" "+" "+" "*")))
+      (my-correct-symbol-bounds (my-ligature-list ligs #Xe100))))
+```