Make an interpreter for yes!

10

2

Yes is a stack-based language that has a few space-separated instructions:

yes: Push 1 to the stack
no: Push 0 to the stack
what: Push the input to the stack (input is taken at the start of program execution and is the same for the whole execution)
sure: Increment the last item in the stack
nah: Decrement the last item in the stack
really: If the last stack item is a number, replace it with its Unicode character. If it is a letter, replace it with its Unicode char code.
oh: convert the stack to strings and concatenate it, and push that to the stack.
nope: remove the first stack item
yep: remove the last stack item

The stack's last element is always outputted at program end. All non-alphanumeric and non-space characters are ignored. All code is lowercase. Example programs:

yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
oh

prints Hello, World!.

what

prints the input (cat program.)

no nah

prints -1.

no really

prints the NUL character (U+0000)

what 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
oh

prints the input and an underscore.

yes no nope

prints 0

yes no yep

prints 1.

You must write an interpreter in as few bytes as possible. Here's a JS implementation (not well golfed!):

function yes(code, input){
 var stack = [];
 var functions = {
  "yes": "stack.push(1)",
  "no": "stack.push(0)",
  "what": "stack.push(input)",
  "sure": "stack[stack.length - 1] ++",
  "nah": "stack[stack.length - 1] --",
  "really": "stack[stack.length - 1] = (typeof lastItem === 'number' ? String.fromCharCode(lastItem) : lastItem.charCodeAt())",
  "oh": "stack.push(stack.reduce((x, y)=>''+x+y))",
  "nope": "stack.shift()",
  "yep": "stack.pop()"
 };
 code.replace(/[^a-z ]/g, "").split(" ").map(x=>(lastItem = stack[stack.length - 1],eval(functions[x])));
 return stack[stack.length - 1];
}
textarea{
  display: block;
}
Code: <textarea id = "code"></textarea>
Input: <textarea id = "input"></textarea>
<button onclick = "output.value = yes(code.value, input.value)">Run</button>
<textarea id = "output"></textarea>

See also my JS answer below.

You may assume that all integers involved will be less than or equal to 126, that really will never be run with a multi-char string on top of the stack, and that the stack will never be longer than 100 elements.

Edge cases

  • yes yes oh prints 11.
  • Intput may be a string or number.
  • The code can contain any chars. Ones not matching [a-z ] should be ignored.

programmer5000

Posted 2017-05-06T12:52:52.333

Reputation: 7 828

1Please make sure that your testcases include all of the commands. – Leaky Nun – 2017-05-06T12:54:37.700

@LeakyNun done. – programmer5000 – 2017-05-06T13:01:15.007

2What type of integers should be used? Is there overflow? What does really do if there is a multi-character string on top of the stack? – Martin Ender – 2017-05-06T13:03:23.490

@MartinEnder see edits. – programmer5000 – 2017-05-06T13:09:07.713

What does really do if -1 is on the top of the stack? – Leaky Nun – 2017-05-06T13:35:04.510

Can input be taken as an array of strings containing the keywords? – Luke – 2017-05-06T13:35:34.340

What should yes yes oh output? – Leaky Nun – 2017-05-06T13:54:37.943

@LeakyNun undefined behavior (both) – programmer5000 – 2017-05-06T14:00:26.930

@Luke no, you can't. – programmer5000 – 2017-05-06T14:01:03.550

1@programmer5000 Shouldn't yes yes oh print 11? – user41805 – 2017-05-06T14:05:50.000

@programmer5000 Can you include the relevant definitions to your question so that we are clear that what I asked is undefined behaviour? – Leaky Nun – 2017-05-06T14:10:27.700

Can you take code input as a space separated list? – Luke – 2017-05-06T14:11:51.497

1Is it okay if we assume that the input only contains can character in [a-zA-Z ]? – user41805 – 2017-05-06T14:14:02.103

What if you pop from an empty stack? Can we error? – Rɪᴋᴇʀ – 2017-05-06T14:24:30.247

1Push the input Can input be numbers? Arrays? Chars? Strings? If so, can input strings be multi-line? Increment the last item in the stack What does this do when the last item is not a number? – Luis Mendo – 2017-05-06T15:02:44.153

@KritixiLithos it would probably need to be [a-zA-Z\d ], but that's just a guess. – Rɪᴋᴇʀ – 2017-05-06T16:12:27.347

Can we also assume that the stack will not be empty at the end? – Titus – 2017-05-18T18:16:24.740

@Titus no, you can't. – programmer5000 – 2017-05-18T18:16:43.840

Considering your yes yes oh result, I assume that convert to strings means converting a number to its string representation, not to its Unicode. – Titus – 2017-05-18T18:21:59.317

@Titus yes, you are right. – programmer5000 – 2017-05-18T18:22:22.867

Answers

4

05AB1E, 77 67 63 61 bytes

Að«Ã#vyÇO§}ðý•9ǝ×н}ÀÀÙ™Íð•650в"X ¾ I > < DdiçëÇ} J r\r \"#:.V

Assumes the program is on the top of the stack.

Try it online!

Okx

Posted 2017-05-06T12:52:52.333

Reputation: 15 025

Can you really assume that all input is valid? For example that you can't get the program yes no sey yep – Emigna – 2017-05-08T11:36:59.577

@Emigna There are no test cases about this, no specifications, and the OP hasn't clarified this even after somebody has left a comment. – Okx – 2017-05-08T12:14:02.833

I noticed a lack of test-cases. Didn't see anything in the comments about this so I wondered as his reference program ignores invalid commands while yours might execute them as valid commands if the sum of the character codes matches a valid command. – Emigna – 2017-05-08T12:22:58.517

9

JavaScript (ES6), 218 215 204 203 bytes

Takes the program string s and the input i in currying syntax (s)(i).

s=>i=>s.replace(/\w+/g,S=>(c=eval("[P()];P()+1;[s.shift()];1;0;s=[s.join``];P()-1;i;P()[0]?k.charCodeAt():String.fromCharCode(k)".split`;`[parseInt(S,35)%156%9])).map||s.push(c),s=[],P=_=>k=s.pop())&&P()

How?

We use the perfect hash function parseInt(S, 35) % 156 % 9 to convert the instruction S into an index in 0…8 and use this index to select the JS code to be executed:

instruction | base 35 -> dec. | % 156 | % 9 | JS code
------------+-----------------+-------+-----+---------------------------------------------
"yes"       |           42168 |    48 |   3 | 1
"no"        |             829 |    49 |   4 | 0
"what"      |         1393204 |   124 |   7 | i
"sure"      |         1238209 |    37 |   1 | P()+1
"nah"       |           28542 |   150 |   6 | P()-1
"really"    |      1439554619 |    35 |   8 | P()[0]?k.charCodeAt():String.fromCharCode(k)
"oh"        |             857 |    77 |   5 | s=[s.join``]
"nope"      |         1016414 |    74 |   2 | [s.shift()]
"yep"       |           42165 |    45 |   0 | [P()]

The P function pops the last item off the stack s and loads it into k.

We prevent the result of some instructions from being pushed back onto the stack by testing if the .map() method is defined, that is, if the result is an array. The code for oh is returning an array by design and we force nope and yep to return arrays as well. Hence the syntax:

(c = eval("[code0];code1;...".split`;`[index])).map || s.push(c)

Test cases

let f =

s=>i=>s.replace(/\w+/g,S=>(c=eval("[P()];P()+1;[s.shift()];1;0;s=[s.join``];P()-1;i;P()[0]?k.charCodeAt():String.fromCharCode(k)".split`;`[parseInt(S,35)%156%9])).map||s.push(c),s=[],P=_=>k=s.pop())&&P()

console.log(f(`yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
oh`)())

console.log(f(`what`)(1234))

console.log(JSON.stringify(f(`no really`)()))

console.log(f(`what 
yes sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure sure really 
oh`)('code golf'))

console.log(f(`yes no nope`)())

console.log(f(`yes no yep`)())

Arnauld

Posted 2017-05-06T12:52:52.333

Reputation: 111 334

5

Röda, 256 bytes

f c,n{s=[];(c/`\W|_`)()|{|m|s+=#m-2 if[m=~"yes|no"];s[-1]+=#m*2-7 if[m=~"sure|nah"];s+=n if[m="what"];s=s[#m%3:#s-#m%2]if[m=~"nope|yep"];{s+=""s()|s[-1].=_}if[m="oh"];{t=s[-1]y=t..""a=t+0;a=a..""{s[-1]=ord(s)}if[#a>#y]else{s[-1]=chr(t)}}if[#m=6]}_;[s[-1]]}

Try it online!

Explanation

#variable returns the length of variable (if it is a string or an array).

f c,n{                         /*declare a function f with arguments c and n*/
s=[];                          /*initialise the stack*/
(c/`\W|_`)                     /*split the code on anything not [a-zA-Z0-9]*/
          ()|                  /*and push each of its values to the stream*/
{|m|...}_                      /*for each element m in the stream, do:*/
s+=#m-2 if[m=~"yes|no"];       /* add 1 or 0 to the stack if m is "yes" or "no"*/
s[-1]+=#m*2-7if[m=~"sure|nah"];/* increment or decrement the top element if m is "sure" or "nah"*/
s+=n if[m="what"];             /* push input if m is "what"*/
s=s[#m%3:#s-#m%2]              /* remove the first or last element of the stack
  if[m=~"nope|yep"];           /* if m is "nope" or "yep" */
{                 }if[m="oh"]; /* if m is "oh" do:*/
 s+=""                         /*  add an element to the stack*/
      s()|s[-1].=_             /*  for each element in s, concatenate that amount to the last element of the stack*/
{                   }if[#m=6]  /* if m is "really" (it's length is 6) do:*/
 t=s[-1]y=t..""                /*  get the last element of the stack*/
 a=t+0;a=a..""                 /*  add 0 to it, if a is a number, this does nothing, otherwise this makes a longer by 1 character*/
 {s[-1]=ord(s)}if[#a>#y]       /*  if a is longer than t (the last element is a char/string) replace it with its code point*/
 else{s[-1]=chr(t)}            /*  otherwise, replace the last element with the char it represents*/
 [s[-1]]                       /*finally output the top of the stack*/

user41805

Posted 2017-05-06T12:52:52.333

Reputation: 16 320

3

Pyth, 69 bytes

Vczd=Y.v@c"+YsY X_1Y1 +Yw  +Y0 X_1Y_1    PY   +Y1 tY +PYCeY"d%CN23;eY

Try it online!

Leaky Nun

Posted 2017-05-06T12:52:52.333

Reputation: 45 011

Doesn't seem to work on the "Hello, World" program. – Okx – 2017-05-08T08:12:10.187

@Okx It does work; I changed the program in my link; the original program is too long. – Leaky Nun – 2017-05-08T08:12:35.863

Or a bunch of other programs, for that matter. 013456789yes 012345678no oh prints 0, expected output is 10. – Okx – 2017-05-08T08:15:11.153

Also doesn't work for the edge case yes yes oh (specified in the question), expected output is 11. – Okx – 2017-05-08T09:10:55.727

@Okx Look at the comments. The OP specifically specified this as undefined behaviour. – Leaky Nun – 2017-05-08T09:11:51.470

Well, comments don't specify the question. In the question it states that yes yes oh should output 11. – Okx – 2017-05-08T09:12:35.197

1

JS (ES6), 361 340 bytes

c=>i=>(s=[],r="s[s.length-1]",c.replace(/[^a-z ]/g,"").split` `.map(x=>(eval({"yes":"s.push(1)","no":"s.push(0)","what":"s.push(i)","sure":"~++","nah":"~--","really":"~=((typeof ~)[0]<'o'?String.fromCharCode(~):lastItem.charCodeAt())","oh":"s.push(s.reduce((x,y)=>''+x+y))","nope":"s.shift()","yep":"s.pop()"}[x].replace(/~/g,r)))),eval(r))

Takes code and input through currying.

var yes = 
c=>i=>(s=[],r="s[s.length-1]",c.replace(/[^a-z ]/g,"").split` `.map(x=>(eval({"yes":"s.push(1)","no":"s.push(0)","what":"s.push(i)","sure":"~++","nah":"~--","really":"~=((typeof ~)[0]<'o'?String.fromCharCode(~):lastItem.charCodeAt())","oh":"s.push(s.reduce((x,y)=>''+x+y))","nope":"s.shift()","yep":"s.pop()"}[x].replace(/~/g,r)))),eval(r))
textarea{
  display: block;
}
Code: <textarea id = "code"></textarea>
Input: <textarea id = "input"></textarea>
<button onclick = "output.value = yes(code.value)(input.value)">Run</button>
<textarea id = "output"></textarea>

programmer5000

Posted 2017-05-06T12:52:52.333

Reputation: 7 828

1

JavaScript (ES6), 220 216 bytes

c=>i=>c.replace(/\w+/g,x=>a=a.concat(eval("Q,[]  (b=Q)[0]?b.charCodeAt():String.fromCharCode(b) 1    [a.join``,a=[]][0] Q+1 a.shift(),[]  i  Q-1".split`Q`.join`a.pop()`.split` `[parseInt(x,36)%19]||0)),a=[])&&a.pop()

A function that takes input with currying syntax, like f(code)(input).

ETHproductions

Posted 2017-05-06T12:52:52.333

Reputation: 47 880

1

Python 2, 258 bytes

s=[]
m=-1
i,p=input()
for c in p.split(' '):
 k=c<"o"
 if c in"yesnowhat":s+=[i if"w"==c[0]else-k+1]
 if c in"surenah":s[m]+=[1,m][k]
 if"p"in c:s.pop(k-1)
 if"oh"==c:s+=[''.join(map(str,s))]
 if"y"==c[m]:s[m]="'"in`s[m]`and ord(s[m])or chr(s[m])
print(s[m])

Try it online!

-3 bytes thanks to @Wondercricket

ovs

Posted 2017-05-06T12:52:52.333

Reputation: 21 408

1You can save 4 bytes by storing -1 as a variable – Wondercricket – 2017-05-06T16:23:08.320

1

Perl 6,  233  225 bytes

{my @s;{yes=>{@s.push(1)},no=>{@s.push(0)},what=>{@s.push: once slurp},sure=>{++@s.tail},nah=>{--@s.tail},really=>{($/:=@s.tail)~~Int??$/.=chr!!$/.=ord},oh=>{@s.=join},nope=>{@s.shift},yep=>{@s.pop},}{.words}.map:{.()};@s.tail.print}

Try it
Hello World
cat
-1
nul
cat_
0
1 

{my @s;{es=>{@s.push(1)},no=>{@s.push(0)},at=>{@s.push: once slurp},re=>{++@s.tail},ah=>{--@s.tail},ly=>->{($_:=@s.tail)~~Int??.=chr!!.=ord},oh=>{@s.=join},pe=>{@s.shift},ep=>{@s.pop},}{.comb(/..»/)}.map:{.()};@s.tail.print}

Works the same except it only grabs the last two characters from each command, and uses $_ instead of $/ for really.

Try it (Hello World)

Expanded:

{
  my @s; # stack

  {  # Associative array
    yes    => {@s.push(1)},
    no     => {@s.push(0)},
    what   => {@s.push: once slurp}, # read everything from $*IN
    sure   => {++@s.tail},
    nah    => {--@s.tail},
    really => {
          ( $/ := @s.tail ) # bind $/ to the last value in the stack
          ~~ Int            # if that is an Int
      ??  $/.=chr           # replace it with that character
      !!  $/.=ord           # otherwise replace it with its ordinal
    },
    oh     => {@s.=join},
    nope   => {@s.shift},
    yep    => {@s.pop},
  }\
  { .words }                # index by the words in the program
  .map: {.()};              # call each of the lambdas in order

  @s.tail.print             # print the last value on the stack
}

Brad Gilbert b2gills

Posted 2017-05-06T12:52:52.333

Reputation: 12 713

1

PHP, 315 305 bytes

second draft, not tested yet

foreach($argv as$k=>$v)if($k>1)eval((strstr($c=preg_replace('#[^a-z ]#','',$v),p)?'':'$s[]=').[yes=>1,no=>0,what=>'$argv[1]',sure=>'array_pop($s)+1',nah:'array_pop($s)-1',really=>'is_int($x=array_pop($s))?chr($x):ord($x)',oh=>'join($s)',nope=>'array_shift($s)',yep=>'array_pop($s)'][$c].';');echo end($s);

Run with php -nr '<php-code>' <input> <yes-code>.

breakdown

foreach($argv as$k=>$v)if($k>1)         # loop through commands
    eval(                                   # 3. interprete
        (strstr(                            # 2. if no 'p' in command, prepend '$s[]='
                                            # 1. ignore all non-code characters
            $c=preg_replace('#[^a-z ]#','',$v),p)?'':'$s[]=').
        [yes=>1,                                # yes: append 1
        no=>0,                                  # no: append 0
        what=>'$argv[1]',                       # what: append input
        sure=>'array_pop($s)+1',                # sure: remove end, increment, append
        nah:'array_pop($s)-1',                  # nah: remove end, decrement, append
                                                # really: convert between ascii and ordinal
        really=>'is_int($x=array_pop($s))?chr($x):ord($x)',
        oh=>'join($s)',                         # oh: concatenate elements, append
        nope=>'array_shift($s)',                # nope: remove first element
        yep=>'array_pop($s)']                   # yep: remove last element
        [$c]
    .';');
echo end($s);                           # print last element (if exists)

Titus

Posted 2017-05-06T12:52:52.333

Reputation: 13 814

Asked: 2017-05-06T12:52:52.333

Viewed: 656 times

Active: 2017-05-18T19:13:57.910