array-next-num-index.patch

   1 Subject: Helper syntax for arrays with numerical indexes
   2
   3 Working with arrays which have only numerical indexes is a little
   4 cumbersome.  Especially to append/push an element to the end of the array.
   5
   6   arr[@]
   7
   8 gives an index which is one greater than all used numerical indexes in the
   9 array arr.  If none numerical index is used, 0 is returned.
  10
  11   arr[@] = expr
  12
  13 assigns expr to the array at position arr[@].
  14
  15 ---
  16
  17  source/interpret.c |   91 +++++++++++++++++++++++++++++++++++++++++++++++++++++
  18  source/ops.h       |    2 +
  19  source/parse.y     |    6 +++
  20  3 files changed, 99 insertions(+)
  21
  22 diff --quilt old/source/interpret.c new/source/interpret.c
  23 --- old/source/interpret.c
  24 +++ new/source/interpret.c
  25 @@ -3262,10 +3262,31 @@ SparseArrayEntry *arrayIterateNext(Spars
  26          nextPos = NULL;
  27      }
  28      return(nextPos);
  29  }
  30
  31 +static int arrayMaxNumIdx(DataValue *theArray)
  32 +{
  33 +    int maxKey = -1;
  34 +    SparseArrayEntry *iter;
  35 +
  36 +    iter = arrayIterateFirst(theArray);
  37 +    while (iter) {
  38 +        int thisKey;
  39 +
  40 +        if (StringToNum(iter->key, &thisKey)) {
  41 +            /* the rbTree is sorted, but "10" < "2" */
  42 +            if (thisKey > maxKey)
  43 +                maxKey = thisKey;
  44 +        }
  45 +
  46 +        iter = arrayIterateNext(iter);
  47 +    }
  48 +
  49 +    return maxKey;
  50 +}
  51 +
  52  /*
  53  ** evaluate an array element and push the result onto the stack
  54  **
  55  ** Before: Prog->  [nDim], next, ...
  56  **         TheStack-> indnDim, ... ind1, ArraySym, next, ...
  57 @@ -4090,10 +4111,80 @@ static int typeOfOut(void)
  58
  59      return STAT_OK;
  60  }
  61
  62  /*
  63 +** assign to the next numerical index array element of a referenced
  64 +** array on the stack
  65 +**
  66 +** Before: Prog->  next, ...
  67 +**         TheStack-> rhs, ArraySym, next, ...
  68 +** After:  Prog->  next, ... (unchanged)
  69 +**         TheStack-> next, ...
  70 +*/
  71 +static int arrayAssignNext(void)
  72 +{
  73 +    char *keyString = NULL;
  74 +    DataValue srcValue, dstArray;
  75 +    int errNum;
  76 +
  77 +    DISASM_RT(PC-1, 1);
  78 +    STACKDUMP(0, 3);
  79 +
  80 +    POP(srcValue);
  81 +    POP(dstArray);
  82 +
  83 +    if (dstArray.tag != ARRAY_TAG && dstArray.tag != NO_TAG) {
  84 +        return execError("cannot assign array element of non-array", NULL);
  85 +    }
  86 +
  87 +    if (srcValue.tag == ARRAY_TAG) {
  88 +        DataValue arrayCopyValue;
  89 +
  90 +        errNum = ArrayCopy(&arrayCopyValue, &srcValue);
  91 +        srcValue = arrayCopyValue;
  92 +        if (errNum != STAT_OK) {
  93 +            return errNum;
  94 +        }
  95 +    }
  96 +
  97 +    keyString = AllocStringOfNumber(arrayMaxNumIdx(&dstArray) + 1);
  98 +
  99 +    if (!ArrayInsert(&dstArray, keyString, &srcValue)) {
 100 +        return execError("array member allocation failure", NULL);
 101 +    }
 102 +
 103 +    return STAT_OK;
 104 +}
 105 +
 106 +/*
 107 +** return the free numeric index that is greater than all others
 108 +**
 109 +** Before: Prog->  next, ...
 110 +**         TheStack-> ArraySym, next, ...
 111 +** After:  Prog->  next, ... (unchanged)
 112 +**         TheStack-> numIdx, next, ...
 113 +*/
 114 +static int arrayNextNumIdx(void)
 115 +{
 116 +    DataValue srcArray;
 117 +    SparseArrayEntry *iter;
 118 +
 119 +    DISASM_RT(PC-1, 1);
 120 +    STACKDUMP(0, 3);
 121 +
 122 +    POP(srcArray);
 123 +    if (srcArray.tag != ARRAY_TAG) {
 124 +        return execError("operator [@] on non-array", NULL);
 125 +    }
 126 +
 127 +    PUSH_INT(arrayMaxNumIdx(&srcArray) + 1);
 128 +
 129 +    return STAT_OK;
 130 +}
 131 +
 132 +/*
 133  ** checks errno after operations which can set it.  If an error occured,
 134  ** creates appropriate error messages and returns false
 135  */
 136  static int errCheck(const char *s)
 137  {
 138 diff --quilt old/source/parse.y new/source/parse.y
 139 --- old/source/parse.y
 140 +++ new/source/parse.y
 141 @@ -444,10 +444,13 @@ simpstmt:   /* simple variable assignmen
 142              | incrdecr blank initarraylv dot field {
 143                  ADD_OP(OP_ARRAY_REF_ASSIGN_SETUP); ADD_IMMED(0); ADD_IMMED(1);
 144                  ADD_OP($1);
 145                  ADD_OP(OP_ARRAY_ASSIGN); ADD_IMMED(1);
 146              }
 147 +            | initarraylv '[' '@' ']' '=' blank expr {
 148 +                ADD_OP(OP_ARRAY_ASSIGN_NEXT);
 149 +            }
 150              | funccall
 151              ;
 152
 153  evalsym:    SYMBOL {
 154                  $$ = $1; ADD_OP(OP_PUSH_SYM); ADD_SYM($1);
 155 @@ -662,10 +665,13 @@ numexpr:      '(' blank expr blank ')'
 156                  ADD_OP(OP_ARRAY_REF); ADD_IMMED($3);
 157              }
 158              | numexpr dot field {
 159                  ADD_OP(OP_ARRAY_REF); ADD_IMMED(1);
 160              }
 161 +            | numexpr '[' '@' ']' {
 162 +                ADD_OP(OP_ARRAY_NEXT_NUM_IDX);
 163 +            }
 164              | '-' blank numexpr %prec UNARY_MINUS { ADD_OP(OP_NEGATE); }
 165              | NOT blank numexpr                   { ADD_OP(OP_NOT); }
 166              | numexpr '+' blank numexpr           { ADD_OP(OP_ADD); }
 167              | numexpr '-' blank numexpr           { ADD_OP(OP_SUB); }
 168              | numexpr '*' blank numexpr           { ADD_OP(OP_MUL); }
 169 diff --quilt old/source/ops.h new/source/ops.h
 170 --- old/source/ops.h
 171 +++ new/source/ops.h
 172 @@ -37,20 +37,22 @@ OP(BRANCH,                 branch)
 173  OP(BRANCH_TRUE,            branchTrue)     /* off */ /* pop(v), if v: PC += off */
 174  OP(BRANCH_FALSE,           branchFalse)    /* off */ /* pop(v), if !v: PC += off */
 175  OP(BRANCH_NEVER,           branchNever)    /* off */ /*  */
 176  OP(ARRAY_REF,              arrayRef)         /* N */ /* pop(kN..k1,a), push(a[k1..kN]) */
 177  OP(ARRAY_ASSIGN,           arrayAssign)      /* N */ /* pop(v,kN..k1,a), a[k1..kN]=v */
 178 +OP(ARRAY_ASSIGN_NEXT,      arrayAssignNext)          /* pop(v, a), a[a.nextidx] = v */
 179  OP(BEGIN_ARRAY_ITER,       beginArrayIter)  /* it */ /* pop(a), it=a.begin */
 180  OP(ARRAY_ITER,             arrayIter) /*w,k[,v],it,pc*/ /* it?(k.v=it.k,(w?v.v=it.v:),it++):PC=pc */
 181  OP(ARRAY_MULTI_ITER,       arrayMultiIter) /*w,N,k1..kN[,v],it,pc*/ /* while it: (if dim(it.k)==N: ([k1..kN].v=it.k,(w?v.v=it.v:),break), it++), if notfound: PC=pc */
 182  OP(BEGIN_ARRAY_MULTI_ITER_ARRAY, beginArrayMultiIterArray) /*it*/ /*  */
 183  OP(ARRAY_MULTI_ITER_ARRAY, arrayMultiIterArray) /*w,k[v],pc*/ /* top(N) */
 184  OP(IN_ARRAY,               inArray)                  /* pop(a,k), push(a[k]?1:0) */
 185  OP(ARRAY_INDEX,            arrayIndex)       /* N */ /* pop(kN..k1), push([kN..k1]) */
 186  OP(ARRAY_DELETE,           deleteArrayElement) /*N*/ /* N>0 ? (pop(kN..k1,a), del(a[k])) : (pop(a), delall(a)) */
 187  OP(PUSH_ARRAY_SYM,         pushArraySymVal)  /*s,i*/ /* if i: s.v=ary()), push(s.v) */
 188  OP(ARRAY_REF_ASSIGN_SETUP, arrayRefAndAssignSetup) /*op,N*/ /* pop(v,kN..a), a[k1..kN] op= v */
 189 +OP(ARRAY_NEXT_NUM_IDX,     arrayNextNumIdx)          /* pop(a), push(a.nextidx) */
 190  OP(PUSH_ARG,               pushArgVal)               /* pop(num), push($num) */
 191  OP(PUSH_ARG_COUNT,         pushArgCount)             /* push($n_args) */
 192  OP(PUSH_ARG_ARRAY,         pushArgArray)             /* push($args) */
 193  OP(ANONARRAY_OPEN,         anonArrayOpen)            /* push(0), push(ary()) */
 194  OP(ANONARRAY_SKIP,         anonArraySkip)            /* pop(a,n), push(n+1,a) */