diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt index b397328bc0..321da32bf0 100644 --- a/runtime/doc/eval.txt +++ b/runtime/doc/eval.txt @@ -1047,7 +1047,8 @@ expr8(expr1, ...) |Funcref| function call When expr8 is a |Funcref| type variable, invoke the function it refers to. -expr8->name([args]) method call *method* +expr8->name([args]) method call *method* *->* +expr8->{lambda}([args]) For methods that are also available as global functions this is the same as: > name(expr8 [, args]) @@ -1057,6 +1058,9 @@ This allows for chaining, passing the value that one method returns to the next method: > mylist->filter(filterexpr)->map(mapexpr)->sort()->join() < +Example of using a lambda: > + GetPercentage->{x -> x * 100}()->printf('%d%%') + *E274* "->name(" must not contain white space. There can be white space before the "->" and after the "(", thus you can split the lines like this: > diff --git a/src/nvim/eval.c b/src/nvim/eval.c index 23a0ef8506..3646222b91 100644 --- a/src/nvim/eval.c +++ b/src/nvim/eval.c @@ -65,6 +65,8 @@ static char *e_missbrac = N_("E111: Missing ']'"); static char *e_dictrange = N_("E719: Cannot use [:] with a Dictionary"); static char *e_illvar = N_("E461: Illegal variable name: %s"); static char *e_cannot_mod = N_("E995: Cannot modify existing variable"); +static char *e_nowhitespace + = N_("E274: No white space allowed before parenthesis"); static char *e_invalwindow = N_("E957: Invalid window number"); static char *e_lock_unlock = N_("E940: Cannot lock or unlock variable %s"); @@ -4100,6 +4102,90 @@ static int eval7( return ret; } +/// Call the function referred to in "rettv". +/// @param lua_funcname If `rettv` refers to a v:lua function, this must point +/// to the name of the Lua function to call (after the +/// "v:lua." prefix). +/// @return OK on success, FAIL on failure. +static int call_func_rettv(char_u **const arg, + typval_T *const rettv, + const bool evaluate, + dict_T *const selfdict, + typval_T *const basetv, + const char_u *const lua_funcname) + FUNC_ATTR_NONNULL_ARG(1, 2) +{ + partial_T *pt = NULL; + typval_T functv; + const char_u *funcname; + bool is_lua = false; + + // need to copy the funcref so that we can clear rettv + if (evaluate) { + functv = *rettv; + rettv->v_type = VAR_UNKNOWN; + + // Invoke the function. Recursive! + if (functv.v_type == VAR_PARTIAL) { + pt = functv.vval.v_partial; + is_lua = is_luafunc(pt); + funcname = is_lua ? lua_funcname : partial_name(pt); + } else { + funcname = functv.vval.v_string; + } + } else { + funcname = (char_u *)""; + } + + funcexe_T funcexe = FUNCEXE_INIT; + funcexe.firstline = curwin->w_cursor.lnum; + funcexe.lastline = curwin->w_cursor.lnum; + funcexe.evaluate = evaluate; + funcexe.partial = pt; + funcexe.selfdict = selfdict; + funcexe.basetv = basetv; + const int ret = get_func_tv(funcname, is_lua ? *arg - funcname : -1, rettv, + (char_u **)arg, &funcexe); + + // Clear the funcref afterwards, so that deleting it while + // evaluating the arguments is possible (see test55). + if (evaluate) { + tv_clear(&functv); + } + + return ret; +} + +/// Evaluate "->method()". +/// @param verbose if true, give error messages. +/// @note "*arg" points to the '-'. +/// @return FAIL or OK. @note "*arg" is advanced to after the ')'. +static int eval_lambda(char_u **const arg, typval_T *const rettv, + const bool evaluate, const bool verbose) + FUNC_ATTR_NONNULL_ALL +{ + // Skip over the ->. + *arg += 2; + typval_T base = *rettv; + rettv->v_type = VAR_UNKNOWN; + + const int ret = get_lambda_tv(arg, rettv, evaluate); + if (ret == NOTDONE) { + return FAIL; + } else if (**arg != '(') { + if (verbose) { + if (*skipwhite(*arg) == '(') { + EMSG(_(e_nowhitespace)); + } else { + EMSG2(_(e_missingparen), "lambda"); + } + } + tv_clear(rettv); + return FAIL; + } + return call_func_rettv(arg, rettv, evaluate, NULL, &base, NULL); +} + /// Evaluate "->method()". /// @note "*arg" points to the '-'. /// @return FAIL or OK. "*arg" is advanced to after the ')'. @@ -4136,7 +4222,7 @@ static int eval_method(char_u **const arg, typval_T *const rettv, ret = FAIL; } else if (ascii_iswhite((*arg)[-1])) { if (verbose) { - EMSG(_("E274: No white space allowed before parenthesis")); + EMSG(_(e_nowhitespace)); } ret = FAIL; } else { @@ -8509,11 +8595,8 @@ handle_subscript( ) { int ret = OK; - dict_T *selfdict = NULL; - const char_u *s; - typval_T functv; - int slen = 0; - bool lua = false; + dict_T *selfdict = NULL; + const char_u *lua_funcname = NULL; if (tv_is_luafunc(rettv)) { if (**arg != '.') { @@ -8522,14 +8605,13 @@ handle_subscript( } else { (*arg)++; - lua = true; - s = (char_u *)(*arg); - slen = check_luafunc_name(*arg, true); - if (slen == 0) { + lua_funcname = (char_u *)(*arg); + const int len = check_luafunc_name(*arg, true); + if (len == 0) { tv_clear(rettv); ret = FAIL; } - (*arg) += slen; + (*arg) += len; } } @@ -8539,42 +8621,12 @@ handle_subscript( && !ascii_iswhite(*(*arg - 1))) || (**arg == '-' && (*arg)[1] == '>'))) { if (**arg == '(') { - partial_T *pt = NULL; - // need to copy the funcref so that we can clear rettv - if (evaluate) { - functv = *rettv; - rettv->v_type = VAR_UNKNOWN; + ret = call_func_rettv((char_u **)arg, rettv, evaluate, selfdict, NULL, + lua_funcname); - // Invoke the function. Recursive! - if (functv.v_type == VAR_PARTIAL) { - pt = functv.vval.v_partial; - if (!lua) { - s = partial_name(pt); - } - } else { - s = functv.vval.v_string; - } - } else { - s = (char_u *)""; - } - - funcexe_T funcexe = FUNCEXE_INIT; - funcexe.firstline = curwin->w_cursor.lnum; - funcexe.lastline = curwin->w_cursor.lnum; - funcexe.evaluate = evaluate; - funcexe.partial = pt; - funcexe.selfdict = selfdict; - ret = get_func_tv(s, lua ? slen : -1, rettv, (char_u **)arg, &funcexe); - - // Clear the funcref afterwards, so that deleting it while - // evaluating the arguments is possible (see test55). - if (evaluate) { - tv_clear(&functv); - } - - /* Stop the expression evaluation when immediately aborting on - * error, or when an interrupt occurred or an exception was thrown - * but not caught. */ + // Stop the expression evaluation when immediately aborting on + // error, or when an interrupt occurred or an exception was thrown + // but not caught. if (aborting()) { if (ret == OK) { tv_clear(rettv); @@ -8584,9 +8636,12 @@ handle_subscript( tv_dict_unref(selfdict); selfdict = NULL; } else if (**arg == '-') { - if (eval_method((char_u **)arg, rettv, evaluate, verbose) == FAIL) { - tv_clear(rettv); - ret = FAIL; + if ((*arg)[2] == '{') { + // expr->{lambda}() + ret = eval_lambda((char_u **)arg, rettv, evaluate, verbose); + } else { + // expr->name() + ret = eval_method((char_u **)arg, rettv, evaluate, verbose); } } else { // **arg == '[' || **arg == '.' tv_dict_unref(selfdict); diff --git a/src/nvim/testdir/test_method.vim b/src/nvim/testdir/test_method.vim index 58e86131dc..4788f211e8 100644 --- a/src/nvim/testdir/test_method.vim +++ b/src/nvim/testdir/test_method.vim @@ -128,4 +128,14 @@ func Test_method_syntax() call assert_fails('eval [1, 2, 3]-> sort ()', 'E260:') endfunc +func Test_method_lambda() + eval "text"->{x -> x .. " extended"}()->assert_equal('text extended') + eval "text"->{x, y -> x .. " extended " .. y}('more')->assert_equal('text extended more') + + call assert_fails('eval "text"->{x -> x .. " extended"} ()', 'E274:') + + " todo: lambda accepts more arguments than it consumes + " call assert_fails('eval "text"->{x -> x .. " extended"}("more")', 'E99:') +endfunc + " vim: shiftwidth=2 sts=2 expandtab