@material-ui/core/es/utils/capitalize.js

React components that implement Google's Material Design.

import { formatMuiErrorMessage as _formatMuiErrorMessage } from "@material-ui/utils";
// It should to be noted that this function isn't equivalent to `text-transform: capitalize`.
//
// A strict capitalization should uppercase the first letter of each word a the sentence.
// We only handle the first word.
export default function capitalize(string) {
  if (typeof string !== 'string') {
    throw new Error(process.env.NODE_ENV !== "production" ? `Material-UI: capitalize(string) expects a string argument.` : _formatMuiErrorMessage(7));
  }

  return string.charAt(0).toUpperCase() + string.slice(1);
}