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"),t("p",[s._v("跟传统的"),t("code",[s._v("try/catch")]),s._v("代码块不同的是，如果没有使用"),t("code",[s._v("catch")]),s._v("方法指定错误处理的回调函数，Promise 对象抛出的错误不会传递到外层代码，即不会有任何反应。")]),s._v(" "),t("div",{staticClass:"language-javascript line-numbers-mode"},[t("pre",{pre:!0,attrs:{class:"language-javascript"}},[t("code",[t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("const")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token function-variable function"}},[s._v("someAsyncThing")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token operator"}},[s._v("=")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("function")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("(")]),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v(")")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token punctuation"}},[s._v("{")]),s._v("\n "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("return")]),s._v(" "),t("span",{pre:!0,attrs:{class:"token keyword"}},[s._v("new")]),s._v(" 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(in promise) ReferenceError: x is not defined // 报错却不退出进程")]),s._v("\n"),t("span",{pre:!0,attrs:{class:"token comment"}},[s._v("// 123")]),s._v("\n")])]),s._v(" 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