76f09b1e49
Modern javascript has a short-hand for function properties, embrace it for better readability and to prepare for an eventual port to ES6 classes. https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/23
35 lines
1.0 KiB
JavaScript
35 lines
1.0 KiB
JavaScript
// -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
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// parse:
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// @params: caller-provided parameter object, or %null
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// @defaults-provided defaults object
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// @allowExtras: whether or not to allow properties not in @default
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//
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// Examines @params and fills in default values from @defaults for
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// any properties in @defaults that don't appear in @params. If
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// @allowExtras is not %true, it will throw an error if @params
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// contains any properties that aren't in @defaults.
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//
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// If @params is %null, this returns the values from @defaults.
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//
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// Return value: a new object, containing the merged parameters from
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// @params and @defaults
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function parse(params, defaults, allowExtras) {
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let ret = {}, prop;
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if (!params)
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params = {};
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for (prop in params) {
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if (!(prop in defaults) && !allowExtras)
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throw new Error('Unrecognized parameter "' + prop + '"');
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ret[prop] = params[prop];
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}
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for (prop in defaults) {
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if (!(prop in params))
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ret[prop] = defaults[prop];
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}
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return ret;
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} |