Patch 9.0.1053
Problem: Default constructor arguments are not optional.
Solution: Use "= v:none" to make constructor arguments optional.
Files: runtime/doc/vim9class.txt, src/errors.h, src/userfunc.c,
src/vim9class.c, src/vim9compile.c, src/vim9execute.c,
src/vim9instr.c, src/proto/vim9instr.pro, src/vim9.h,
src/testdir/test_vim9_class.vim
*** ../vim-9.0.1052/runtime/doc/vim9class.txt 2022-12-08 15:32:11.075034154
+0000
--- runtime/doc/vim9class.txt 2022-12-13 18:41:05.293974808 +0000
***************
*** 96,102 ****
this.col = col
enddef
endclass
!
You can create an object from this class with the new() method: >
var pos = TextPosition.new(1, 1)
--- 96,102 ----
this.col = col
enddef
endclass
! < *object* *Object*
You can create an object from this class with the new() method: >
var pos = TextPosition.new(1, 1)
***************
*** 104,110 ****
The object members "lnum" and "col" can be accessed directly: >
echo $'The text position is ({pos.lnum}, {pos.col})'
!
If you have been using other object-oriented languages you will notice that
in Vim the object members are consistently referred to with the "this."
prefix. This is different from languages like Java and TypeScript. This
--- 104,110 ----
The object members "lnum" and "col" can be accessed directly: >
echo $'The text position is ({pos.lnum}, {pos.col})'
! < *E1317* *E1327*
If you have been using other object-oriented languages you will notice that
in Vim the object members are consistently referred to with the "this."
prefix. This is different from languages like Java and TypeScript. This
***************
*** 329,342 ****
==============================================================================
! 5. More class details *Vim9-class*
Defining a class ~
*:class* *:endclass* *:abstract*
A class is defined between `:class` and `:endclass`. The whole class is
defined in one script file. It is not possible to add to a class later.
! A class can only be defined in a |Vim9| script file. *E1315*
A class cannot be defined inside a function.
It is possible to define more than one class in a script file. Although it
--- 329,342 ----
==============================================================================
! 5. More class details *Vim9-class* *Class*
*class*
Defining a class ~
*:class* *:endclass* *:abstract*
A class is defined between `:class` and `:endclass`. The whole class is
defined in one script file. It is not possible to add to a class later.
! A class can only be defined in a |Vim9| script file. *E1316*
A class cannot be defined inside a function.
It is possible to define more than one class in a script file. Although it
***************
*** 361,367 ****
*E1314*
The class name should be CamelCased. It must start with an uppercase letter.
That avoids clashing with builtin types.
!
After the class name these optional items can be used. Each can appear only
once. They can appear in any order, although this order is recommended: >
extends ClassName
--- 361,367 ----
*E1314*
The class name should be CamelCased. It must start with an uppercase letter.
That avoids clashing with builtin types.
! *E1315*
After the class name these optional items can be used. Each can appear only
once. They can appear in any order, although this order is recommended: >
extends ClassName
***************
*** 377,382 ****
--- 377,396 ----
interface, which is often done in many languages, especially Java.
+ Items in a class ~
+ *E1318* *E1325* *E1326*
+ Inside a class, in betweeen `:class` and `:endclass`, these items can appear:
+ - An object member declaration: >
+ this._memberName: memberType
+ this.memberName: memberType
+ public this.memberName: memberType
+ - A constructor method: >
+ def new(arguments)
+ def newName(arguments)
+ - An object method: >
+ def SomeMethod(arguments)
+
+
Defining an interface ~
*:interface* *:endinterface*
An interface is defined between `:interface` and `:endinterface`. It may be
***************
*** 417,427 ****
Then The default constructor will be: >
! def new(this.name, this.age, this.gender)
enddef
All object members will be used, also private access ones.
Multiple constructors ~
--- 431,462 ----
Then The default constructor will be: >
! def new(this.name = v:none, this.age = v:none, this.gender = v:none)
enddef
All object members will be used, also private access ones.
+ The "= v:none" default values make the arguments optional. Thus you can also
+ call `new()` without any arguments. No assignment will happen and the default
+ value for the object members will be used. This is a more useful example,
+ with default values: >
+
+ class TextPosition
+ this.lnum: number = 1
+ this.col: number = 1
+ endclass
+
+ If you want the constructor to have mandatory arguments, you need to write it
+ yourself. For example, if for the AutoNew class above you insist on getting
+ the name, you can define the constructor like this: >
+
+ def new(this.name, this.age = v:none, this.gender = v:none)
+ enddef
+ < *E1328*
+ Note that you cannot use another default value than "v:none" here. If you
+ want to initialize the object members, do it where they are declared. This
+ way you only need to look in one place for the default values.
+
Multiple constructors ~
*** ../vim-9.0.1052/src/errors.h 2022-12-09 21:41:43.904327284 +0000
--- src/errors.h 2022-12-13 15:46:28.110463023 +0000
***************
*** 3372,3375 ****
--- 3372,3377 ----
INIT(= N_("E1326: Member not found on object \"%s\": %s"));
EXTERN char e_object_required_found_str[]
INIT(= N_("E1327: Object required, found %s"));
+ EXTERN char e_constructor_default_value_must_be_vnone_str[]
+ INIT(= N_("E1328: Constructor default value must be v:none: %s"));
#endif
*** ../vim-9.0.1052/src/userfunc.c 2022-12-10 18:42:09.094378801 +0000
--- src/userfunc.c 2022-12-13 17:05:23.549043681 +0000
***************
*** 224,230 ****
char_u *p;
int c;
int any_default = FALSE;
- char_u *expr;
char_u *whitep = *argp;
if (newargs != NULL)
--- 224,229 ----
***************
*** 302,307 ****
--- 301,334 ----
arg = p;
while (ASCII_ISALNUM(*p) || *p == '_')
++p;
+ char_u *argend = p;
+
+ if (*skipwhite(p) == '=')
+ {
+ char_u *defval = skipwhite(skipwhite(p) + 1);
+ if (STRNCMP(defval, "v:none", 6) != 0)
+ {
+ semsg(_(e_constructor_default_value_must_be_vnone_str), p);
+ goto err_ret;
+ }
+ any_default = TRUE;
+ p = defval + 6;
+
+ if (ga_grow(default_args, 1) == FAIL)
+ goto err_ret;
+
+ char_u *expr = vim_strsave((char_u *)"v:none");
+ if (expr == NULL)
+ goto err_ret;
+ ((char_u **)(default_args->ga_data))
+ [default_args->ga_len] = expr;
+ default_args->ga_len++;
+ }
+ else if (any_default)
+ {
+ emsg(_(e_non_default_argument_follows_default_argument));
+ goto err_ret;
+ }
// TODO: check the argument is indeed a member
if (newargs != NULL && ga_grow(newargs, 1) == FAIL)
***************
*** 309,315 ****
if (newargs != NULL)
{
((char_u **)(newargs->ga_data))[newargs->ga_len] =
! vim_strnsave(arg, p - arg);
newargs->ga_len++;
if (argtypes != NULL && ga_grow(argtypes, 1) == OK)
--- 336,342 ----
if (newargs != NULL)
{
((char_u **)(newargs->ga_data))[newargs->ga_len] =
! vim_strnsave(arg, argend - arg);
newargs->ga_len++;
if (argtypes != NULL && ga_grow(argtypes, 1) == OK)
***************
*** 322,336 ****
if (ga_grow(newlines, 1) == OK)
{
// "this.name = name"
! int len = 5 + (p - arg) + 3 + (p - arg) + 1;
char_u *assignment = alloc(len);
if (assignment != NULL)
{
! c = *p;
! *p = NUL;
! vim_snprintf((char *)assignment, len,
"this.%s = %s", arg, arg);
! *p = c;
((char_u **)(newlines->ga_data))[
newlines->ga_len++] = assignment;
}
--- 349,370 ----
if (ga_grow(newlines, 1) == OK)
{
// "this.name = name"
! int len = 5 + (argend - arg) + 3 + (argend - arg) + 1;
! if (any_default)
! len += 14 + 10;
char_u *assignment = alloc(len);
if (assignment != NULL)
{
! c = *argend;
! *argend = NUL;
! if (any_default)
! vim_snprintf((char *)assignment, len,
! "ifargisset %d this.%s = %s",
! default_args->ga_len - 1, arg, arg);
! else
! vim_snprintf((char *)assignment, len,
"this.%s = %s", arg, arg);
! *argend = c;
((char_u **)(newlines->ga_data))[
newlines->ga_len++] = assignment;
}
***************
*** 361,367 ****
// find the end of the expression (doesn't evaluate it)
any_default = TRUE;
p = skipwhite(np + 1);
! expr = p;
if (eval1(&p, &rettv, NULL) != FAIL)
{
if (!skip)
--- 395,401 ----
// find the end of the expression (doesn't evaluate it)
any_default = TRUE;
p = skipwhite(np + 1);
! char_u *expr = p;
if (eval1(&p, &rettv, NULL) != FAIL)
{
if (!skip)
*** ../vim-9.0.1052/src/vim9class.c 2022-12-10 18:42:09.090378817 +0000
--- src/vim9class.c 2022-12-13 17:10:48.921759464 +0000
***************
*** 269,274 ****
--- 269,275 ----
ga_concat(&fga, (char_u *)"this.");
objmember_T *m = cl->class_obj_members + i;
ga_concat(&fga, (char_u *)m->om_name);
+ ga_concat(&fga, (char_u *)" = v:none");
}
ga_concat(&fga, (char_u *)")\nenddef\n");
ga_append(&fga, NUL);
*** ../vim-9.0.1052/src/vim9compile.c 2022-12-10 18:42:09.090378817 +0000
--- src/vim9compile.c 2022-12-13 17:01:53.268332112 +0000
***************
*** 2195,2202 ****
* Return "arg" if it does not look like a variable list.
*/
static char_u *
! compile_assignment(char_u *arg, exarg_T *eap, cmdidx_T cmdidx, cctx_T *cctx)
{
char_u *var_start;
char_u *p;
char_u *end = arg;
--- 2195,2207 ----
* Return "arg" if it does not look like a variable list.
*/
static char_u *
! compile_assignment(
! char_u *arg_start,
! exarg_T *eap,
! cmdidx_T cmdidx,
! cctx_T *cctx)
{
+ char_u *arg = arg_start;
char_u *var_start;
char_u *p;
char_u *end = arg;
***************
*** 2206,2211 ****
--- 2211,2217 ----
int semicolon = 0;
int did_generate_slice = FALSE;
garray_T *instr = &cctx->ctx_instr;
+ int jump_instr_idx = instr->ga_len;
char_u *op;
int oplen = 0;
int heredoc = FALSE;
***************
*** 2216,2221 ****
--- 2222,2244 ----
lhs_T lhs;
long start_lnum = SOURCING_LNUM;
+ int has_arg_is_set_prefix = STRNCMP(arg, "ifargisset ", 11)
== 0;
+ if (has_arg_is_set_prefix)
+ {
+ arg += 11;
+ int def_idx = getdigits(&arg);
+ arg = skipwhite(arg);
+
+ // Use a JUMP_IF_ARG_NOT_SET instruction to skip if the value was not
+ // given and the default value is "v:none".
+ int off = STACK_FRAME_SIZE + (cctx->ctx_ufunc->uf_va_name != NULL
+ ? 1 : 0);
+ int count = cctx->ctx_ufunc->uf_def_args.ga_len;
+ if (generate_JUMP_IF_ARG(cctx, ISN_JUMP_IF_ARG_NOT_SET,
+ def_idx - count - off) == FAIL)
+ goto theend;
+ }
+
// Skip over the "varname" or "[varname, varname]" to get to any "=".
p = skip_var_list(arg, TRUE, &var_count, &semicolon, TRUE);
if (p == NULL)
***************
*** 2636,2641 ****
--- 2659,2671 ----
if (var_idx + 1 < var_count)
var_start = skipwhite(lhs.lhs_end + 1);
+
+ if (has_arg_is_set_prefix)
+ {
+ // set instruction index in JUMP_IF_ARG_SET to here
+ isn_T *isn = ((isn_T *)instr->ga_data) + jump_instr_idx;
+ isn->isn_arg.jumparg.jump_where = instr->ga_len;
+ }
}
// For "[var, var] = expr" drop the "expr" value.
***************
*** 2711,2719 ****
}
}
! if (*eap->cmd == '[')
{
- // might be "[var, var] = expr"
*line = compile_assignment(eap->cmd, eap, CMD_SIZE, cctx);
if (*line == NULL)
return FAIL;
--- 2741,2749 ----
}
}
! // might be "[var, var] = expr" or "ifargisset this.member = expr"
! if (*eap->cmd == '[' || STRNCMP(eap->cmd, "ifargisset ", 11) == 0)
{
*line = compile_assignment(eap->cmd, eap, CMD_SIZE, cctx);
if (*line == NULL)
return FAIL;
***************
*** 2994,3000 ****
int count = ufunc->uf_def_args.ga_len;
int first_def_arg = ufunc->uf_args.ga_len - count;
int i;
- char_u *arg;
int off = STACK_FRAME_SIZE + (ufunc->uf_va_name != NULL ? 1 : 0);
int did_set_arg_type = FALSE;
--- 3024,3029 ----
***************
*** 3002,3024 ****
SOURCING_LNUM = 0; // line number unknown
for (i = 0; i < count; ++i)
{
type_T *val_type;
int arg_idx = first_def_arg + i;
where_T where = WHERE_INIT;
- int r;
int jump_instr_idx = instr->ga_len;
isn_T *isn;
// Use a JUMP_IF_ARG_SET instruction to skip if the value was given.
! if (generate_JUMP_IF_ARG_SET(&cctx, i - count - off) == FAIL)
goto erret;
// Make sure later arguments are not found.
ufunc->uf_args_visible = arg_idx;
! arg = ((char_u **)(ufunc->uf_def_args.ga_data))[i];
! r = compile_expr0(&arg, &cctx);
!
if (r == FAIL)
goto erret;
--- 3031,3057 ----
SOURCING_LNUM = 0; // line number unknown
for (i = 0; i < count; ++i)
{
+ char_u *arg = ((char_u **)(ufunc->uf_def_args.ga_data))[i];
+ if (STRCMP(arg, "v:none") == 0)
+ // "arg = v:none" means the argument is optional without
+ // setting a value when the argument is missing.
+ continue;
+
type_T *val_type;
int arg_idx = first_def_arg + i;
where_T where = WHERE_INIT;
int jump_instr_idx = instr->ga_len;
isn_T *isn;
// Use a JUMP_IF_ARG_SET instruction to skip if the value was given.
! if (generate_JUMP_IF_ARG(&cctx, ISN_JUMP_IF_ARG_SET,
! i - count - off) == FAIL)
goto erret;
// Make sure later arguments are not found.
ufunc->uf_args_visible = arg_idx;
! int r = compile_expr0(&arg, &cctx);
if (r == FAIL)
goto erret;
*** ../vim-9.0.1052/src/vim9execute.c 2022-12-10 18:42:09.090378817 +0000
--- src/vim9execute.c 2022-12-13 18:36:25.062067849 +0000
***************
*** 2068,2074 ****
}
/*
! * Store a value in a list, dict or blob variable.
* Returns OK, FAIL or NOTDONE (uncatchable error).
*/
static int
--- 2068,2074 ----
}
/*
! * Store a value in a list, dict, blob or object variable.
* Returns OK, FAIL or NOTDONE (uncatchable error).
*/
static int
***************
*** 2177,2185 ****
{
long lidx = (long)tv_idx->vval.v_number;
blob_T *blob = tv_dest->vval.v_blob;
! varnumber_T nr;
! int error = FALSE;
! int len;
if (blob == NULL)
{
--- 2177,2185 ----
{
long lidx = (long)tv_idx->vval.v_number;
blob_T *blob = tv_dest->vval.v_blob;
! varnumber_T nr;
! int error = FALSE;
! int len;
if (blob == NULL)
{
***************
*** 2209,2214 ****
--- 2209,2215 ----
long idx = (long)tv_idx->vval.v_number;
object_T *obj = tv_dest->vval.v_object;
typval_T *otv = (typval_T *)(obj + 1);
+ clear_tv(&otv[idx]);
otv[idx] = *tv;
}
else
***************
*** 4293,4302 ****
// Jump if an argument with a default value was already set and not
// v:none.
case ISN_JUMP_IF_ARG_SET:
tv = STACK_TV_VAR(iptr->isn_arg.jumparg.jump_arg_off);
! if (tv->v_type != VAR_UNKNOWN
! && !(tv->v_type == VAR_SPECIAL
! && tv->vval.v_number == VVAL_NONE))
ectx->ec_iidx = iptr->isn_arg.jumparg.jump_where;
break;
--- 4294,4305 ----
// Jump if an argument with a default value was already set and not
// v:none.
case ISN_JUMP_IF_ARG_SET:
+ case ISN_JUMP_IF_ARG_NOT_SET:
tv = STACK_TV_VAR(iptr->isn_arg.jumparg.jump_arg_off);
! int arg_set = tv->v_type != VAR_UNKNOWN
! && !(tv->v_type == VAR_SPECIAL
! && tv->vval.v_number == VVAL_NONE);
! if (iptr->isn_type == ISN_JUMP_IF_ARG_SET ? arg_set : !arg_set)
ectx->ec_iidx = iptr->isn_arg.jumparg.jump_where;
break;
***************
*** 6632,6637 ****
--- 6635,6646 ----
iptr->isn_arg.jumparg.jump_arg_off + STACK_FRAME_SIZE,
iptr->isn_arg.jump.jump_where);
break;
+
+ case ISN_JUMP_IF_ARG_NOT_SET:
+ smsg("%s%4d JUMP_IF_ARG_NOT_SET arg[%d] -> %d", pfx, current,
+ iptr->isn_arg.jumparg.jump_arg_off + STACK_FRAME_SIZE,
+ iptr->isn_arg.jump.jump_where);
+ break;
case ISN_FOR:
{
*** ../vim-9.0.1052/src/vim9instr.c 2022-12-10 18:42:09.094378801 +0000
--- src/vim9instr.c 2022-12-13 16:32:29.707108836 +0000
***************
*** 1408,1422 ****
}
/*
! * Generate an ISN_JUMP_IF_ARG_SET instruction.
*/
int
! generate_JUMP_IF_ARG_SET(cctx_T *cctx, int arg_off)
{
isn_T *isn;
RETURN_OK_IF_SKIP(cctx);
! if ((isn = generate_instr(cctx, ISN_JUMP_IF_ARG_SET)) == NULL)
return FAIL;
isn->isn_arg.jumparg.jump_arg_off = arg_off;
// jump_where is set later
--- 1408,1422 ----
}
/*
! * Generate an ISN_JUMP_IF_ARG_SET or ISN_JUMP_IF_ARG_NOT_SET instruction.
*/
int
! generate_JUMP_IF_ARG(cctx_T *cctx, isntype_T isn_type, int arg_off)
{
isn_T *isn;
RETURN_OK_IF_SKIP(cctx);
! if ((isn = generate_instr(cctx, isn_type)) == NULL)
return FAIL;
isn->isn_arg.jumparg.jump_arg_off = arg_off;
// jump_where is set later
***************
*** 2479,2484 ****
--- 2479,2485 ----
case ISN_GETITEM:
case ISN_GET_OBJ_MEMBER:
case ISN_JUMP:
+ case ISN_JUMP_IF_ARG_NOT_SET:
case ISN_JUMP_IF_ARG_SET:
case ISN_LISTAPPEND:
case ISN_LISTINDEX:
*** ../vim-9.0.1052/src/proto/vim9instr.pro 2022-12-10 18:42:09.094378801
+0000
--- src/proto/vim9instr.pro 2022-12-13 17:01:03.324121725 +0000
***************
*** 47,53 ****
int generate_DEF(cctx_T *cctx, char_u *name, size_t len);
int generate_JUMP(cctx_T *cctx, jumpwhen_T when, int where);
int generate_WHILE(cctx_T *cctx, int funcref_idx);
! int generate_JUMP_IF_ARG_SET(cctx_T *cctx, int arg_off);
int generate_FOR(cctx_T *cctx, int loop_idx);
int generate_ENDLOOP(cctx_T *cctx, loop_info_T *loop_info);
int generate_TRYCONT(cctx_T *cctx, int levels, int where);
--- 47,53 ----
int generate_DEF(cctx_T *cctx, char_u *name, size_t len);
int generate_JUMP(cctx_T *cctx, jumpwhen_T when, int where);
int generate_WHILE(cctx_T *cctx, int funcref_idx);
! int generate_JUMP_IF_ARG(cctx_T *cctx, isntype_T isn_type, int arg_off);
int generate_FOR(cctx_T *cctx, int loop_idx);
int generate_ENDLOOP(cctx_T *cctx, loop_info_T *loop_info);
int generate_TRYCONT(cctx_T *cctx, int levels, int where);
*** ../vim-9.0.1052/src/vim9.h 2022-12-10 18:42:09.094378801 +0000
--- src/vim9.h 2022-12-13 16:33:19.363129186 +0000
***************
*** 124,129 ****
--- 124,131 ----
ISN_JUMP, // jump if condition is matched isn_arg.jump
ISN_JUMP_IF_ARG_SET, // jump if argument is already set, uses
// isn_arg.jumparg
+ ISN_JUMP_IF_ARG_NOT_SET, // jump if argument is not set, uses
+ // isn_arg.jumparg
// loop
ISN_FOR, // get next item from a list, uses isn_arg.forloop
***************
*** 260,266 ****
int jump_where; // position to jump to
} jump_T;
! // arguments to ISN_JUMP_IF_ARG_SET
typedef struct {
int jump_arg_off; // argument index, negative
int jump_where; // position to jump to
--- 262,268 ----
int jump_where; // position to jump to
} jump_T;
! // arguments to ISN_JUMP_IF_ARG_SET and ISN_JUMP_IF_ARG_NOT_SET
typedef struct {
int jump_arg_off; // argument index, negative
int jump_where; // position to jump to
*** ../vim-9.0.1052/src/testdir/test_vim9_class.vim 2022-12-10
19:03:48.044388086 +0000
--- src/testdir/test_vim9_class.vim 2022-12-13 18:37:49.146067719 +0000
***************
*** 182,186 ****
--- 182,237 ----
v9.CheckScriptSuccess(lines)
enddef
+ def Test_class_default_new()
+ var lines =<< trim END
+ vim9script
+
+ class TextPosition
+ this.lnum: number = 1
+ this.col: number = 1
+ endclass
+
+ var pos = TextPosition.new()
+ assert_equal(1, pos.lnum)
+ assert_equal(1, pos.col)
+
+ pos = TextPosition.new(v:none, v:none)
+ assert_equal(1, pos.lnum)
+ assert_equal(1, pos.col)
+
+ pos = TextPosition.new(3, 22)
+ assert_equal(3, pos.lnum)
+ assert_equal(22, pos.col)
+
+ pos = TextPosition.new(v:none, 33)
+ assert_equal(1, pos.lnum)
+ assert_equal(33, pos.col)
+ END
+ v9.CheckScriptSuccess(lines)
+
+ lines =<< trim END
+ vim9script
+ class Person
+ this.name: string
+ this.age: number = 42
+ this.education: string = "unknown"
+
+ def new(this.name, this.age = v:none, this.education = v:none)
+ enddef
+ endclass
+
+ var piet = Person.new("Piet")
+ assert_equal("Piet", piet.name)
+ assert_equal(42, piet.age)
+ assert_equal("unknown", piet.education)
+
+ var chris = Person.new("Chris", 4, "none")
+ assert_equal("Chris", chris.name)
+ assert_equal(4, chris.age)
+ assert_equal("none", chris.education)
+ END
+ v9.CheckScriptSuccess(lines)
+ enddef
+
" vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker
*** ../vim-9.0.1052/src/version.c 2022-12-13 13:42:32.179427634 +0000
--- src/version.c 2022-12-13 18:21:37.554157231 +0000
***************
*** 697,698 ****
--- 697,700 ----
{ /* Add new patch number below this line */
+ /**/
+ 1053,
/**/
--
GALAHAD: No. Look, I can tackle this lot single-handed!
GIRLS: Yes, yes, let him Tackle us single-handed!
"Monty Python and the Holy Grail" PYTHON (MONTY) PICTURES LTD
/// Bram Moolenaar -- [email protected] -- http://www.Moolenaar.net \\\
/// \\\
\\\ sponsor Vim, vote for features -- http://www.Vim.org/sponsor/ ///
\\\ help me help AIDS victims -- http://ICCF-Holland.org ///
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