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node_modules/@riotjs/util/checks.js

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+/**
+ * Quick type checking
+ * @param   {*} element - anything
+ * @param   {string} type - type definition
+ * @returns {boolean} true if the type corresponds
+ */
+export function checkType(element, type) {
+  return typeof element === type
+}
+
+/**
+ * Check if an element is part of an svg
+ * @param   {HTMLElement}  el - element to check
+ * @returns {boolean} true if we are in an svg context
+ */
+export function isSvg(el) {
+  const owner = el.ownerSVGElement
+
+  return !!owner || owner === null
+}
+
+/**
+ * Check if an element is a template tag
+ * @param   {HTMLElement}  el - element to check
+ * @returns {boolean} true if it's a <template>
+ */
+export function isTemplate(el) {
+  return el.tagName.toLowerCase() === 'template'
+}
+
+/**
+ * Check that will be passed if its argument is a function
+ * @param   {*} value - value to check
+ * @returns {boolean} - true if the value is a function
+ */
+export function isFunction(value) {
+  return checkType(value, 'function')
+}
+
+/**
+ * Check if a value is a Boolean
+ * @param   {*}  value - anything
+ * @returns {boolean} true only for the value is a boolean
+ */
+export function isBoolean(value) {
+  return checkType(value, 'boolean')
+}
+
+/**
+ * Check if a value is an Object
+ * @param   {*}  value - anything
+ * @returns {boolean} true only for the value is an object
+ */
+export function isObject(value) {
+  return !isNil(value) && value.constructor === Object
+}
+
+/**
+ * Check if a value is null or undefined
+ * @param   {*}  value - anything
+ * @returns {boolean} true only for the 'undefined' and 'null' types
+ */
+export function isNil(value) {
+  return value === null || value === undefined
+}
+
+/**
+ * Detect node js environements
+ * @returns {boolean} true if the runtime is node
+ */
+export function isNode() {
+  return typeof process !== 'undefined'
+}