Merge pull request #1757 from xexyl/lynn2019

Add 2019/lynn/try.sh, other files, updates

2019/giles/README.md

@@ -51,11 +51,12 @@ under a free license.
 
 This program has also been successfully compiled on Windows, with both the [Tiny
 C Compiler](https://bellard.org/tcc/) and Microsoft's C/C++ compiler. However,
-the latter reports warnings about loss of information when converting floats,
+the latter reports warnings about loss of information when converting `float`s,
 and that `void (*)()` and `void (*)(void)` are not the same thing.
 
 Interesting fact: The size of the program from `./iocccsize -i` is 2019.
 
+
 #### How to use:
 
 ```sh
@@ -98,6 +99,7 @@ print `Bad input file` or `Wave file must be 16 bits,1-2 channels.` depending on
 what it thinks the problem is. If the output file cannot be opened, the program
 will print `Can't open output file`.
 
+
 ### Assumptions:
 
 1. The code is compiled using the C99 or C11 standard.
@@ -107,6 +109,7 @@ represents the number zero.
 4. `int16_t` and `int32_t` are 2's-complement, `sizeof(int16_t) == 2` and
 `sizeof(int32_t) == 4`.
 
+
 ### Obfuscations
 
 The main obfuscation is that digital signal processing algorithms are inherently
@@ -143,8 +146,8 @@ to decipher it.
 `#define`s are used to abbreviate the code, which has a side effect of making it
 very slightly harder to read.
 
-* `k` is just a general-purpose replacement for 16.
+* `k` is just a general-purpose replacement for `16`.
-* `i` is the number of delay-lines to allocate and use (currently 24).
+* `i` is the number of delay-lines to allocate and use (currently `24`).
 * `q` is an abbreviation for multiplying two elements of `w[]` together.
 * `u()` is used to display percentages with proper rounding.
 * `j()` imposes an upper limit on a floating-point value, and then negates it.
@@ -186,7 +189,7 @@ As many values as possible have been crammed into arrays. `float w[]` contains:
 
 All of the strings are concatenated together and "encrypted" by breaking the
 string into 4-byte chunks (by casting it to an `int32_t*`), and then XORing the
-sequence of ints with a known numeric sequence. The "decryption" is not done
+sequence of `int`s with a known numeric sequence. The "decryption" is not done
 in-place, to avoid writing over the string constant.
 
 `int32_t *c` is a pointer that points into `f[]`, except that it is often

2019/karns/Makefile

@@ -68,7 +68,8 @@ CINCLUDE=
 
 # Optimization
 #
-OPT=
+# We disable the optimiser because the entry has problems with it enabled.
+OPT= -O0
 
 # Default flags for ANSI C compilation
 #
@@ -137,8 +138,11 @@ all: data ${TARGET}
 	clean clobber install love haste waste maker easter_egg \
 	sandwich supernova deep_magic magic charon pluto
 
+
+# We FORCE the use of -O0 even if someone overrides it because this entry has
+# problems with it enabled.
 ${PROG}: ${PROG}.c
-	${CC} ${CFLAGS} $< -o $@ ${LDFLAGS}
+	${CC} ${CFLAGS} -O0 $< -o $@ ${LDFLAGS}
 	${LN} -sf ${PROG} tbfs
 
 test: ${PROG}

2019/karns/README.md

@@ -4,6 +4,21 @@
 make
 ```
 
+NOTE: we disable the optimiser because this program has problems with it
+enabled.
+
+
+### Bugs and (Mis)features:
+
+The current status of this entry is:
+
+```
+STATUS: INABIAF - please **DO NOT** fix
+```
+
+For more detailed information see [2019 karns in bugs.md](/bugs.md#2019-karns).
+
+
 
 ## To use:
 
@@ -11,22 +26,25 @@ make
 ./prog < textfile_that_fits_on_the_screen
 ```
 
+You might want to type:
+
+```sh
+reset
+```
+
+after running the program to restore the terminal to its previous state.
+
 
 ### Try:
 
 ```sh
-./prog < README.md
+./try.sh
-
-./prog < prog.c
-
-./prog < maze
 ```
 
-The last two can be done in a sequence, first showing the respective files at
+If you have more time you might want to try:
-the terminal, like:
 
 ```sh
-./try.sh
+./prog < README.md
 ```
 
 
@@ -37,10 +55,10 @@ not, YMMV -- teach you how to find your way in a maze. The algorithm is
 well-known but the drawing is amazing!
 
 Before running, make sure that your terminal can accommodate the whole file.
-Before running "make test", make it about 120x40 to be safe, ensuring that you
+Before running `make test`, make it about 120x40 to be safe, ensuring that you
-see the @ sign as well as the exclamation mark.
+see the `@` sign as well as the exclamation mark.
 
-...Oh, and the first M in YMMV stands for "mazing".
+...Oh, and the first `M` in YMMV stands for "mazing".
 
 A puzzle for the reader: Can you change the program to consider a diagonal
 movement as one step?
@@ -50,15 +68,17 @@ movement as one step?
 
 ### The Program:
 
-This program is pretty simple! It performs a breadth first search on the
+This program is pretty simple! It performs a [breadth first
-specified graph. The graph can be any ascii text file  that has an 'at'
+search](https://en.wikipedia.org/wiki/Breadth-first_search) on the
-character, which is going to be the starting location, and a '!' character
+specified graph. The graph can be any ASCII text file that has an 'at' (`@`)
+character, which is going to be the starting location, and a `!` character
 which will be the destination.
 
 The nodes on this graph that are spaces are connected with any directly
 adjacent nodes that are also spaces. Nodes that aren't spaces are not
 connected with anything.
 
+
 ### Compiling and Running:
 
 This program usually compiles under both GCC and clang. Build with:
@@ -67,7 +87,7 @@ This program usually compiles under both GCC and clang. Build with:
 $(CC) -std=c99 -o tbfs prog.c
 ```
 
-where $(CC) is cc, gcc, clang, or some other c compiler.
+where `$(CC)` is cc, gcc, clang, or some other C compiler.
 
 You can then run it with:
 

2019/karns/try.sh

@@ -1,8 +1,6 @@
 #!/usr/bin/env bash
 #
-# Demo of IOCCC 26 (2019) 'Most in need of whitespace' entry by Joshua Karns.
+# try.sh - demonstrate IOCCC winner 2019/karns
-#
-# Doesn't run the program on README.md as it's longer and slower.
 #
 
 # make sure CC is set so that when we do make CC="$CC" it isn't empty. Doing it
@@ -20,13 +18,11 @@ clear
 # display prog.c to the user
 echo "$ cat prog.c"
 cat prog.c
-sleep 2
 
-# run the program on itself
+# run the program on its own source code
-echo "$ ./prog < prog.c"
+read -r -n 1 -p "Press any key to run: ./prog < prog.c: "
-sleep 2
+echo 1>&2
 ./prog < prog.c
-sleep 2
 
 # reset terminal for colours
 reset
@@ -34,13 +30,12 @@ reset
 # display maze
 echo "$ cat maze"
 cat maze
-sleep 2
 
 # run the program on maze
-echo "$ ./prog < maze"
+read -r -n 1 -p "Press any key to run: ./prog < maze: "
-sleep 2
+echo 1>&2
 ./prog < maze
 
-sleep 2
+read -r -n 1 -p "Press any key to exit: "
 # reset terminal
 reset

2019/lynn/.gitignore

@@ -3,6 +3,9 @@
 *.dSYM
 fib
 fib.c
+ghcfib
+ghcfib.hi
+ghcfib.o
 hint
 hint.c
 indent

2019/lynn/README.md

@@ -5,6 +5,17 @@ make
 ```
 
 
+### Bugs and (Mis)features:
+
+The current status of this entry is:
+
+```
+STATUS: INABIAF - please **DO NOT** fix
+```
+
+For more detailed information see [2019 lynn in bugs.md](/bugs.md#2019-lynn).
+
+
 ## To use:
 
 ```sh
@@ -15,15 +26,14 @@ make
 ### Try:
 
 ```sh
-(./prog < fib.hs; cat prog.c) > fib.c
+./try.sh
-cc fib.c -o fib
-./fib
 ```
 
 
 ## Judges' remarks:
 
-A fully functional compiler. The example prints out the 30th Fibonacci number.
+A fully functional compiler. The example prints out the 30th [Fibonacci
+number](https://en.wikipedia.org/wiki/Fibonacci_sequence).
 
 
 ## Author's remarks:
@@ -39,7 +49,7 @@ system? The solution is simple: no type checking. It also means no
 typeclasses. Just pass dictionaries explicitly.
 
  * `ZeroPauseGarbageCollection`: Instead of disruptive stop-the-world garbage
- collection, we only tidy up when the world stops of its own accord, that is,
+ collection, we only tidy up when the world stops on its own accord, that is,
  on program termination.
 
  * `OneHundredPercentPure`: Gone is the catch-all lawless IO monad. And no
@@ -47,6 +57,7 @@ typeclasses. Just pass dictionaries explicitly.
 
  * `SyntaxForTheMasses`: See below.
 
+
 ### Building:
 
 Build the compiler:
@@ -59,7 +70,7 @@ cc -o prog prog.c
 
 #### Fibonacci numbers:
 
-Test the compiler on `fib.hs`:
+Test the compiler on [fib.hs](fib.hs):
 
 ```sh
 (./prog < fib.hs ; cat prog.c) > fib.c
@@ -67,19 +78,20 @@ Test the compiler on `fib.hs`:
 
 Compiling the output produces a binary that prints the 30th Fibonacci number.
 
-The file `ghcfib.hs` includes `fib.hs` with some glue code, and shows GHC also
+The file [ghcfib.hs](ghcfib.hs) includes [fib.hs](fib.hs) with some glue code,
-accepts our subset of Haskell:
+and shows GHC also accepts our subset of Haskell:
 
 ```sh
- ghc ghcfib.hs
+ghc ghcfib.hs
 ```
 
+
 #### Self-hosting compiler:
 
 To avoid spoiling this entry by revealing the original Haskell source, we
-instead provide `hint.hs`, the output of a certain stage of the compiler when
+instead provide [hint.hs](hint.hs), the output of a certain stage of the
-run on itself. This intermediate output is hopefully difficult to understand,
+compiler when run on itself. This intermediate output is hopefully difficult to
-yet is accepted by our compiler:
+understand, yet is accepted by our compiler:
 
 ```sh
 (./prog < hint.hs ; cat prog.c) > hint.c
@@ -90,13 +102,15 @@ make hint
 The output program behaves like the compiler itself.
 
 Unlike the original source from which it is derived, GHC fails to compile
-`hint.hs`. This is because values have been replaced with their Scott encodings
+[hint.hs](hint.hs). This is because values have been replaced with their [Scott
+encodings](https://en.wikipedia.org/wiki/Mogensen-Scott_encoding)
 by this stage, which messes up type-checks; we'd need `equirecursive` types for
 it to work.
 
+
 #### Regexes:
 
-The file `lol.hs` contains an adaptation of [Doug McIlroy's elegant code from
+The file [lol.hs](lol.hs) contains an adaptation of [Doug McIlroy's elegant code from
 "Enumerating the strings of regular
 languages"](https://www.cs.dartmouth.edu/~doug/nfa.pdf). We exercise it by
 showing the first entries of the length-ordered list of all strings consisting
@@ -114,10 +128,12 @@ A GHC wrapper is provided:
 ghc ghclol.hs
 ```
 
+
 ### Strongly-connected components:
 
-See `scc.hs` (and its GHC wrapper `ghcscc.hs`) for an elegant way to print the
+See [scc.hs](scc.hs) (and its GHC wrapper [ghcscc.hs](ghcscc.hs)) for an elegant
-strongly-connected components of a graph in reverse topological order.
+way to print the strongly-connected components of a graph in reverse topological
+order.
 
 ```sh
 (./prog < scc.hs ; cat prog.c) > scc.c
@@ -128,15 +144,16 @@ It expects the input to be in a similar format as a previous entry
 
 ```sh
 make scc
-./scc < ../../2018/vokes/example-1.txt
+./scc < example-1.txt
-./scc < ../../2018/vokes/example-2.txt
+./scc < example-2.txt
 ```
 
 The output should agree, though our program omits line numbers and does not
 sort entries within a line. (Also, our program only treats spaces as
 whitespace, and supports any non-space character in a vertex name.)
 
-### Syntax ###
+
+### Syntax
 
 Some claim Haskell syntax is frightening because braces and semicolons are
 optional. Some complain about a zoo of twisty little operators, all alike. Our
@@ -144,11 +161,13 @@ compiler addresses such concerns by making braces and semicolons compulsory,
 disabling layout-based rules, making every operator left-associative with same
 precedence, and only defining 6 primitive functions:
 
-    : + - * / <=
+```
+: + - * / <=
+```
 
-The arithmetic operations behave as they do in C on unsigned ints, and `(:)` is
+The arithmetic operations behave as they do in C on `unsigned int`s, and `(:)` is
-Haskell's cons function. Like Haskell and unlike C, `(<=)` returns a Bool
+Haskell's `cons` function. Like Haskell and unlike C, `(<=)` returns a `Bool`
-(which are Church booleans behind the scenes) and not an Int.
+(which are Church booleans behind the scenes) and not an `Int`.
 
 No ifs, ands, or buts. Define them yourself. No tuples. Who needs them when
 algebraic data types delivers a better product? There is no do. No where. No
@@ -160,11 +179,12 @@ Within global scope or a let expression, each definition can only refer to
 itself or previous definitions. This implies we can only achieve mutual
 recursion by having one function pass itself to others.
 
-### Caveats ###
+
+### Caveats
 
 The only primitive type is `Int`. In particular, they represent characters. To
 interoperate with GHC, our compiler treats any undefined functions as the
-identity function, so that we may freely use `ord` and `chr` (or `fromEnum` and
+`identity` function, so that we may freely use `ord` and `chr` (or `fromEnum` and
 `toEnum`) to make our code acceptable to both compilers.
 
 The main function is the last function to successfully parse. It should have
@@ -172,7 +192,7 @@ type `[Int] -> [Int]`, and our compiler treats this like the function passed
 into `Prelude.interact`, that is, the entire standard input is passed to this
 function, and the result is printed to standard output.
 
-Bool must be defined as:
+`Bool` must be defined as:
 
 ```
 data Bool = True | False;
@@ -181,14 +201,14 @@ data Bool = True | False;
 so that it matches the Scott-encoded booleans internally used by the primitive
 function `(<=)`.
 
-The alternatives in a case expressions must list every data constructor in
+The alternatives in a `case` expressions must list every data constructor in
 the order they are defined. For example, if we have:
 
 ```
 data Foo a b = Bar a | Baz | Qux Int [b]
 ```
 
-then a case expression that examines a term of this type must have the form:
+then a `case` expression that examines a term of this type must have the form:
 
 ```
 case x of
@@ -203,9 +223,10 @@ semicolons as separators, not terminators.
 
 The effect of erroneous input is undefined. It may be best to develop with GHC,
 but even then, be mindful of changes needed because of issues caused by the
-uniform operator precedence and the touchy format of case alternatives.
+uniform operator precedence and the touchy format of `case` alternatives.
 
-### Why? ###
+
+### Why?
 
 One-letter variable names abound in IOCCC entries, and for good reason. These
 tiny pieces of confetti are hard to read, and leave room for more code. Then
@@ -221,6 +242,7 @@ or rather, a compiler that accepts a subset of Haskell sufficiently large to
 self-host. You might say I wrote a tool for this contest, then ran it on itself
 to make an entry for it.
 
+
 ### Obfuscation techniques:
 
 Even with Kiselyov's algorithm and some term rewriting, the compiler only fit
@@ -236,7 +258,7 @@ ternary operators, and so on.
 * Huffman coding.
 * Base-85 because high bits are frowned upon.
 * Mixed radix encoding to game iocccsize. From a past winner
-([2018/bellard](/2018/bellard/prog.c)), it seems 9 11 12 32 are the only
+([2018/bellard](/2018/bellard/README.md)), it seems 9 11 12 32 are the only
 whitespace octets that may appear verbatim in string literals.
 * Choosing what to encode in Huffman/base-85 and what to encode in mixed radix
 was a delicate balancing act. In the end, I only had a few bytes to spare, which
@@ -244,16 +266,16 @@ I spent on gratuitous confusion.
 * The effects of some functions depend on the order their arguments are
 evaluated, yet the program works either way. Why?
 * Ugly macros for the runtime system's jump table for lazy reduction. A previous
-winner ([2013/endoh1](/2013/endoh1/endoh1.c)) has a cuter solution, which I
+winner ([2013/endoh1](/2013/endoh1/README.md)) has a cuter solution, which I
 avoid because of originality concerns and also because my combinators are
 compressed.
 * Relies on the inability of C comments to nest.
-* Cheaper and more complicated to print comma-separated ints (and header and
+* Cheaper and more complicated to print comma-separated `int`s (and header and
 footer) in C.
 * Primitive functions use a trick described in depth by [Naylor and Runciman,
 "The Reduceron reconfigured and
 re-evaluated"](https://www.cs.york.ac.uk/fp/reduceron/jfp-reduceron.pdf). We
-represent the integer n with a term equivalent to `Y(BT)n`; it works because
+represent the integer `n` with a term equivalent to `Y(BT)n`; it works because
 `Y(BT)ne = e(Y(BT)n)`.
 * A sentinel in the heap often confused me, so ought to confuse others.
 
@@ -263,19 +285,20 @@ compiler. See [hint.hs](hint.hs).
  * Mercilessly point-free. Everything is a combinator.
  * Scott encoding. Everything is a combinator.
  * Sum types are oddly ordered and may even contain unused data constructors to
- reduce code duplication. (In C terms, unions may have extra fields, and they're
+ reduce code duplication. (In C terms, `union`s may have extra fields, and they're
  ordered in such a way so we can reuse code to access certain fields.)
  * The `undefined` function compiles to the `(.)` function.
  * Replaced the only `(&&)` with `(||)` and `not` using De Morgan's law, which
  makes some comparisons less comprehensible.
  * [Kiselyov only published "&#955; to SKI, Semantically" last
  year](http://okmij.org/ftp/tagless-final/ski.pdf).
- * Recursion via the fixpoint (Y) combinator, which is represented by the
+ * Recursion via the fixpoint (`Y`) combinator, which is represented by the
  variable `""` during one stage of compilation.
  * Involves theory that may be less familiar to C programmers: maps, folds,
  parser combinators, lambda calculus, bracket abstraction, denotational
  semantics, etc.
 
+
 ### Warnings:
 
 On my system, it compiles cleanly with `-Wall` with older standards, e.g.
@@ -284,6 +307,7 @@ On my system, it compiles cleanly with `-Wall` with older standards, e.g.
 Compiling the compiler output with `-Wall` triggers a warning about a
 strange-looking comment.
 
+
 ### Behind-the-scenes commentary:
 
 [My website reveals how this compiler

2019/lynn/example-1.txt

@@ -0,0 +1,8 @@
+0 4 8
+1 0
+2 1 3
+3 2
+4 1
+5 4 6
+6 5 2
+7 3 6 7

2019/lynn/example-2.txt

@@ -0,0 +1,8 @@
+0 1
+1 2 4 5
+2 3 6
+3 2 7
+4 0 5
+5 6 5
+6 5
+7 3 6

2019/lynn/try.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+#
+# try.sh - demonstrate IOCCC winner 2019/lynn
+#
+
+# make sure CC is set so that when we do make CC="$CC" it isn't empty. Doing it
+# this way allows us to have the user specify a different compiler in an easy
+# way.
+if [[ -z "$CC" ]]; then
+    CC="cc"
+fi
+
+make CC="$CC" all >/dev/null || exit 1
+
+# clear screen after compilation so that only the entry is shown
+clear
+
+echo "$ (./prog < fib.hs; cat prog.c) > fib.c" 1>&2
+(./prog < fib.hs; cat prog.c) > fib.c
+echo "$ cc -Wno-everything fib.c -o fib" 1>&2
+cc -Wno-everything fib.c -o fib
+echo "$ ./fib" 1>&2
+./fib
+echo 1>&2
+read -r -n 1 -p "Press any key to continue: "
+echo 1>&2
+
+echo "$ (./prog < lol.hs ; cat prog.c) > lol.c" 1>&2
+(./prog < lol.hs ; cat prog.c) > lol.c
+echo "$ make lol" 1>&2
+make lol
+read -r -n 1 -p "Press any key to run: ./lol: "
+echo 1>&2
+./lol
+echo 1>&2
+
+read -r -n 1 -p "Press any key to continue: "
+echo 1>&2
+echo "$ (./prog < scc.hs ; cat prog.c) > scc.c" 1>&2
+(./prog < scc.hs ; cat prog.c) > scc.c
+echo "$ make scc" 1>&2
+make scc
+read -r -n 1 -p "Press any key to run: ./scc < example-1.txt: "
+echo 1>&2
+./scc < example-1.txt
+read -r -n 1 -p "Press any key to run: ./scc < example-2.txt: "
+echo 1>&2
+./scc < example-2.txt
+
+
+exit 0
+

bugs.md

@@ -3466,6 +3466,44 @@ As a backtrace quine this entry is **SUPPOSED to segfault** so this should not b
 touched either.
 
 
+## 2019 karns
+
+### STATUS: INABIAF - please **DO NOT** fix
+### Source code: [2019/karns/prog.c](2019/karns/prog.c)
+### Information: [2019/karns/README.md](2019/karns/README.md)
+
+The author stated the following:
+
+---
+
+- The program must be ran in a terminal that supports ANSI escape codes for
+moving the cursor and changing colors.
+- Segfaults happen sometimes.
+- I don't know what memory management there is, if any.
+- The program will not compile by an ANSI C compiler: it uses for loops, and
+it uses C++ style comments. It should compile cleanly using a C99 standard.
+- Breadth first search is slow (and very slow on certain maps), but my A star
+version of this program is too big.
+- Lots of extra whitespace may be needed if you want to feed in an arbitrary
+file.
+- It fails to compile on GCC sometimes (according to a friend of mine, I've
+not encountered this myself).
+- The program could be obfuscated much further.
+- The program contains some unused code and data.
+
+
+## 2019 lynn
+
+### STATUS: INABIAF - please **DO NOT** fix
+### Source code: [2019/lynn/prog.c](2019/lynn/prog.c)
+### Information: [2019/lynn/README.md](2019/lynn/README.md)
+
+The author wrote that there are a number of differences from what one might
+expect. Rather than duplicate the information we refer you to the author's
+remarks in the sections [Syntax](/2019/lynn/README.md#syntax) and
+[Caveats](/2019/lynn/README.md#caveats).
+
+
 ## 2019 poikola
 
 ### STATUS: INABIAF - please **DO NOT** fix

thanks-for-help.md

@@ -4233,6 +4233,16 @@ He also added the script [try.sh](/2019/karns/try.sh) to showcase the entry a
 bit more easily.
 
 
+## <a name="2019_lynn"></a>[2019/lynn](/2019/lynn/prog.c) ([README.md](/2019/lynn/README.md]))
+
+[Cody](#cody) added the [try.sh](/2019/lynn/try.sh) script.
+
+Cody also added the [example-1.txt](/2019/lynn/example-1.txt) and
+[example-2.txt](/2019/lynn/example-2.txt) text files from
+[2018/vokes](/2018/vokes/README.md) so that the entry does not rely on any other
+entry existing.
+
+
 ## <a name="2019_yang"></a>[2019/yang](/2019/yang/prog.c) ([README.md](/2019/yang/README.md]))
 
 [Cody](#cody) added the [try.sh](/2019/yang/try.sh) script which also involved