flow like the river

VISUALIZACION/node_modules/graphql/language/lexer.d.ts

@@ -0,0 +1,58 @@
+import { Token } from './ast';
+import { Source } from './source';
+import { TokenKindEnum } from './tokenKind';
+
+/**
+ * Given a Source object, this returns a Lexer for that source.
+ * A Lexer is a stateful stream generator in that every time
+ * it is advanced, it returns the next token in the Source. Assuming the
+ * source lexes, the final Token emitted by the lexer will be of kind
+ * EOF, after which the lexer will repeatedly return the same EOF token
+ * whenever called.
+ */
+export class Lexer {
+  source: Source;
+
+  /**
+   * The previously focused non-ignored token.
+   */
+  lastToken: Token;
+
+  /**
+   * The currently focused non-ignored token.
+   */
+  token: Token;
+
+  /**
+   * The (1-indexed) line containing the current token.
+   */
+  line: number;
+
+  /**
+   * The character offset at which the current line begins.
+   */
+  lineStart: number;
+
+  constructor(source: Source);
+
+  /**
+   * Advances the token stream to the next non-ignored token.
+   */
+  advance(): Token;
+
+  /**
+   * Looks ahead and returns the next non-ignored token, but does not change
+   * the state of Lexer.
+   */
+  lookahead(): Token;
+}
+
+/**
+ * @internal
+ */
+export function isPunctuatorToken(token: Token): boolean;
+
+/**
+ * @internal
+ */
+export function isPunctuatorTokenKind(kind: TokenKindEnum): boolean;