MIRROR: javascript for 🐜's, a tiny runtime with big ambitions
nullish coalescing operator
+288
-4
+1
-1
meson.build
+1
-1
meson.build
···
41
41
build_date = run_command('date', '+%Y-%m-%d', check: true).stdout().strip()
42
42
43
43
version_conf = configuration_data()
44
-
version_conf.set('ANT_VERSION', '0.0.5.47')
44
+
version_conf.set('ANT_VERSION', '0.0.5.48')
45
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version_conf.set('ANT_GIT_HASH', git_hash)
46
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version_conf.set('ANT_BUILD_DATE', build_date)
47
47
+24
-3
src/ant.c
+24
-3
src/ant.c
···
117
117
TOK_TYPEOF, TOK_UPLUS, TOK_UMINUS, TOK_EXP, TOK_MUL, TOK_DIV, TOK_REM,
118
118
TOK_OPTIONAL_CHAIN, TOK_REST,
119
119
TOK_PLUS, TOK_MINUS, TOK_SHL, TOK_SHR, TOK_ZSHR, TOK_LT, TOK_LE, TOK_GT,
120
-
TOK_GE, TOK_EQ, TOK_NE, TOK_AND, TOK_XOR, TOK_OR, TOK_LAND, TOK_LOR,
120
+
TOK_GE, TOK_EQ, TOK_NE, TOK_AND, TOK_XOR, TOK_OR, TOK_LAND, TOK_LOR, TOK_NULLISH,
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TOK_COLON, TOK_Q, TOK_ASSIGN, TOK_PLUS_ASSIGN, TOK_MINUS_ASSIGN,
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TOK_MUL_ASSIGN, TOK_DIV_ASSIGN, TOK_REM_ASSIGN, TOK_SHL_ASSIGN,
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123
TOK_SHR_ASSIGN, TOK_ZSHR_ASSIGN, TOK_AND_ASSIGN, TOK_XOR_ASSIGN,
···
904
904
#define LOOK(OFS, CH) js->toff + OFS < js->clen && buf[OFS] == CH
905
905
906
906
switch (buf[0]) {
907
-
case '?': if (LOOK(1, '.')) TOK(TOK_OPTIONAL_CHAIN, 2); TOK(TOK_Q, 1);
907
+
case '?': if (LOOK(1, '?')) TOK(TOK_NULLISH, 2); if (LOOK(1, '.')) TOK(TOK_OPTIONAL_CHAIN, 2); TOK(TOK_Q, 1);
908
908
case ':': TOK(TOK_COLON, 1);
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909
case '(': TOK(TOK_LPAREN, 1);
910
910
case ')': TOK(TOK_RPAREN, 1);
···
2740
2740
LTR_BINOP(js_bitwise_xor, (next(js) == TOK_OR));
2741
2741
}
2742
2742
2743
+
static jsval_t js_nullish_coalesce(struct js *js) {
2744
+
jsval_t res = js_bitwise_or(js);
2745
+
if (is_err(res)) return res;
2746
+
uint8_t flags = js->flags;
2747
+
while (next(js) == TOK_NULLISH) {
2748
+
js->consumed = 1;
2749
+
res = resolveprop(js, res);
2750
+
uint8_t res_type = vtype(res);
2751
+
if (res_type != T_NULL && res_type != T_UNDEF) {
2752
+
js->flags |= F_NOEXEC;
2753
+
}
2754
+
if (js->flags & F_NOEXEC) {
2755
+
js_nullish_coalesce(js);
2756
+
} else {
2757
+
res = js_nullish_coalesce(js);
2758
+
}
2759
+
}
2760
+
js->flags = flags;
2761
+
return res;
2762
+
}
2763
+
2743
2764
static jsval_t js_logical_and(struct js *js) {
2744
-
jsval_t res = js_bitwise_or(js);
2765
+
jsval_t res = js_nullish_coalesce(js);
2745
2766
if (is_err(res)) return res;
2746
2767
uint8_t flags = js->flags;
2747
2768
while (next(js) == TOK_LAND) {
+263
tests/test_ternary_and_operators.cjs
+263
tests/test_ternary_and_operators.cjs
···
1
+
// Test ternary operator (?:), logical OR (||), and nullish coalescing (??)
2
+
3
+
console.log("=== Ternary, Logical OR, and Nullish Coalescing Test ===\n");
4
+
5
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// Test 1: Basic ternary operator
6
+
console.log("Test 1: Basic ternary operator");
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+
let x = 10;
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+
let y = 5;
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+
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let result1 = x > y ? "x is greater" : "y is greater or equal";
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+
console.log(" 10 > 5 ? 'x is greater' : 'y is greater or equal' =>", result1);
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+
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let result2 = x < y ? "x is less" : "x is greater or equal";
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+
console.log(" 10 < 5 ? 'x is less' : 'x is greater or equal' =>", result2);
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+
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let result3 = true ? "yes" : "no";
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console.log(" true ? 'yes' : 'no' =>", result3);
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+
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let result4 = false ? "yes" : "no";
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+
console.log(" false ? 'yes' : 'no' =>", result4);
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+
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// Test 2: Nested ternary operators
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console.log("\nTest 2: Nested ternary operators");
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+
let age = 25;
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+
let category = age < 18 ? "minor" : age < 65 ? "adult" : "senior";
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+
console.log(" age = 25, category:", category);
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+
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+
age = 15;
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category = age < 18 ? "minor" : age < 65 ? "adult" : "senior";
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console.log(" age = 15, category:", category);
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+
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age = 70;
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category = age < 18 ? "minor" : age < 65 ? "adult" : "senior";
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console.log(" age = 70, category:", category);
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+
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// Test 3: Ternary with various types
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console.log("\nTest 3: Ternary with various types");
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let score = 85;
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let grade = score >= 90 ? "A" : score >= 80 ? "B" : score >= 70 ? "C" : "F";
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console.log(" score = 85, grade:", grade);
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+
42
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let hasPermission = true;
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let status = hasPermission ? 200 : 403;
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+
console.log(" hasPermission = true, status:", status);
45
+
46
+
let value = null;
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+
let output = value ? value : "default";
48
+
console.log(" null ? null : 'default' =>", output);
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+
50
+
// Test 4: Logical OR (||) operator
51
+
console.log("\nTest 4: Logical OR (||) operator");
52
+
53
+
// With boolean values
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+
let bool1 = true || false;
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+
let bool2 = false || true;
56
+
let bool3 = false || false;
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+
let bool4 = true || true;
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console.log(" true || false =>", bool1);
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+
console.log(" false || true =>", bool2);
60
+
console.log(" false || false =>", bool3);
61
+
console.log(" true || true =>", bool4);
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+
63
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// Test 5: Logical OR with truthy/falsy values
64
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console.log("\nTest 5: Logical OR with truthy/falsy values");
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let val1 = null || "default";
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let val2 = undefined || "fallback";
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let val3 = "" || "empty string fallback";
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+
let val4 = 0 || 42;
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let val5 = false || true;
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let val6 = "first" || "second";
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let val7 = 100 || 200;
72
+
73
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console.log(" null || 'default' =>", val1);
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+
console.log(" undefined || 'fallback' =>", val2);
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+
console.log(" '' || 'empty string fallback' =>", val3);
76
+
console.log(" 0 || 42 =>", val4);
77
+
console.log(" false || true =>", val5);
78
+
console.log(" 'first' || 'second' =>", val6);
79
+
console.log(" 100 || 200 =>", val7);
80
+
81
+
// Test 6: Chained logical OR
82
+
console.log("\nTest 6: Chained logical OR");
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+
let option1 = null;
84
+
let option2 = undefined;
85
+
let option3 = "";
86
+
let option4 = "valid value";
87
+
let finalValue = option1 || option2 || option3 || option4 || "ultimate fallback";
88
+
console.log(" null || undefined || '' || 'valid value' || 'ultimate fallback' =>", finalValue);
89
+
90
+
let allFalsy = null || undefined || false || 0 || "";
91
+
console.log(" null || undefined || false || 0 || '' =>", allFalsy);
92
+
93
+
// Test 7: Nullish coalescing (??) operator
94
+
console.log("\nTest 7: Nullish coalescing (??) operator");
95
+
96
+
// Basic nullish coalescing
97
+
let nc1 = null ?? "default";
98
+
let nc2 = undefined ?? "fallback";
99
+
let nc3 = "" ?? "empty string fallback";
100
+
let nc4 = 0 ?? 42;
101
+
let nc5 = false ?? true;
102
+
let nc6 = "value" ?? "default";
103
+
104
+
console.log(" null ?? 'default' =>", nc1);
105
+
console.log(" undefined ?? 'fallback' =>", nc2);
106
+
console.log(" '' ?? 'empty string fallback' =>", nc3);
107
+
console.log(" 0 ?? 42 =>", nc4);
108
+
console.log(" false ?? true =>", nc5);
109
+
console.log(" 'value' ?? 'default' =>", nc6);
110
+
111
+
// Test 8: Difference between || and ??
112
+
console.log("\nTest 8: Difference between || and ??");
113
+
console.log(" Comparing || and ?? with various values:");
114
+
115
+
let testVal = 0;
116
+
console.log(" 0 || 'fallback' =>", testVal || "fallback");
117
+
console.log(" 0 ?? 'fallback' =>", testVal ?? "fallback");
118
+
119
+
testVal = "";
120
+
console.log(" '' || 'fallback' =>", testVal || "fallback");
121
+
console.log(" '' ?? 'fallback' =>", testVal ?? "fallback");
122
+
123
+
testVal = false;
124
+
console.log(" false || 'fallback' =>", testVal || "fallback");
125
+
console.log(" false ?? 'fallback' =>", testVal ?? "fallback");
126
+
127
+
testVal = null;
128
+
console.log(" null || 'fallback' =>", testVal || "fallback");
129
+
console.log(" null ?? 'fallback' =>", testVal ?? "fallback");
130
+
131
+
testVal = undefined;
132
+
console.log(" undefined || 'fallback' =>", testVal || "fallback");
133
+
console.log(" undefined ?? 'fallback' =>", testVal ?? "fallback");
134
+
135
+
// Test 9: Chained nullish coalescing
136
+
console.log("\nTest 9: Chained nullish coalescing");
137
+
let config1 = null;
138
+
let config2 = undefined;
139
+
let config3 = "configured";
140
+
let config = config1 ?? config2 ?? config3 ?? "default config";
141
+
console.log(" null ?? undefined ?? 'configured' ?? 'default config' =>", config);
142
+
143
+
let allNull = null ?? undefined ?? null;
144
+
console.log(" null ?? undefined ?? null =>", allNull);
145
+
146
+
// Test 10: Ternary with || and ??
147
+
console.log("\nTest 10: Combining ternary with || and ??");
148
+
let username = null;
149
+
let displayName = username ? username : "Guest";
150
+
console.log(" username = null, ternary result:", displayName);
151
+
152
+
displayName = username || "Guest (using ||)";
153
+
console.log(" username = null, || result:", displayName);
154
+
155
+
displayName = username ?? "Guest (using ??)";
156
+
console.log(" username = null, ?? result:", displayName);
157
+
158
+
username = "";
159
+
displayName = username || "Guest (using ||)";
160
+
console.log(" username = '', || result:", displayName);
161
+
162
+
displayName = username ?? "Guest (using ??)";
163
+
console.log(" username = '', ?? result:", displayName);
164
+
165
+
// Test 11: In conditional expressions
166
+
console.log("\nTest 11: In conditional expressions");
167
+
let a = 5;
168
+
let b = 10;
169
+
170
+
if (a > b ? true : false) {
171
+
console.log(" a > b: true");
172
+
} else {
173
+
console.log(" a > b: false");
174
+
}
175
+
176
+
let condition = null || undefined || "has value";
177
+
if (condition) {
178
+
console.log(" Condition with || is truthy:", condition);
179
+
}
180
+
181
+
let ncCondition = null ?? undefined ?? "has value";
182
+
if (ncCondition) {
183
+
console.log(" Condition with ?? is truthy:", ncCondition);
184
+
}
185
+
186
+
// Test 12: In function returns
187
+
console.log("\nTest 12: In function returns");
188
+
function getMax(x, y) {
189
+
return x > y ? x : y;
190
+
}
191
+
192
+
console.log(" getMax(15, 20):", getMax(15, 20));
193
+
console.log(" getMax(30, 10):", getMax(30, 10));
194
+
195
+
function getFirstValid(a, b, c) {
196
+
return a || b || c || "none";
197
+
}
198
+
199
+
console.log(" getFirstValid(null, '', 'value'):", getFirstValid(null, "", "value"));
200
+
console.log(" getFirstValid(null, undefined, false):", getFirstValid(null, undefined, false));
201
+
202
+
function getFirstNonNullish(a, b, c) {
203
+
return a ?? b ?? c ?? "none";
204
+
}
205
+
206
+
console.log(" getFirstNonNullish(null, '', 'value'):", getFirstNonNullish(null, "", "value"));
207
+
console.log(" getFirstNonNullish(null, undefined, false):", getFirstNonNullish(null, undefined, false));
208
+
209
+
// Test 13: Assignment with operators
210
+
console.log("\nTest 13: Assignment with operators");
211
+
let setting = null;
212
+
let finalSetting = setting ?? "default";
213
+
console.log(" setting = null, finalSetting:", finalSetting);
214
+
215
+
setting = undefined;
216
+
finalSetting = setting ?? "default";
217
+
console.log(" setting = undefined, finalSetting:", finalSetting);
218
+
219
+
setting = 0;
220
+
finalSetting = setting ?? "default";
221
+
console.log(" setting = 0, finalSetting:", finalSetting);
222
+
223
+
// Test 14: With objects and arrays
224
+
console.log("\nTest 14: With objects and arrays");
225
+
let user = null;
226
+
let defaultUser = { name: "Guest", id: 0 };
227
+
let currentUser = user ?? defaultUser;
228
+
console.log(" user = null, currentUser:", currentUser);
229
+
230
+
let items = null;
231
+
let defaultItems = [1, 2, 3];
232
+
let currentItems = items ?? defaultItems;
233
+
console.log(" items = null, currentItems:", currentItems);
234
+
235
+
let emptyArray = [];
236
+
let arrayResult = emptyArray || [1, 2, 3];
237
+
console.log(" [] || [1,2,3] =>", arrayResult);
238
+
239
+
arrayResult = emptyArray ?? [1, 2, 3];
240
+
console.log(" [] ?? [1,2,3] =>", arrayResult);
241
+
242
+
// Test 15: Complex expressions
243
+
console.log("\nTest 15: Complex expressions");
244
+
let min = 10;
245
+
let max = 100;
246
+
let input = 50;
247
+
let clamped = input < min ? min : input > max ? max : input;
248
+
console.log(" Clamping 50 to [10, 100]:", clamped);
249
+
250
+
input = 5;
251
+
clamped = input < min ? min : input > max ? max : input;
252
+
console.log(" Clamping 5 to [10, 100]:", clamped);
253
+
254
+
input = 150;
255
+
clamped = input < min ? min : input > max ? max : input;
256
+
console.log(" Clamping 150 to [10, 100]:", clamped);
257
+
258
+
let priority = null;
259
+
let defaultPriority = 5;
260
+
let finalPriority = (priority ?? defaultPriority) > 10 ? 10 : (priority ?? defaultPriority);
261
+
console.log(" priority = null, clamped to max 10:", finalPriority);
262
+
263
+
console.log("\n=== All tests completed ===");