feat(jmespath): add base types and errors

packages/jmespath/src/Functions.ts

@@ -0,0 +1,4 @@
+// This is a placeholder for the real class. The actual implementation will be added in a subsequent PR.
+export class Functions {
+  public iAmAPlaceholder = true;
+}

packages/jmespath/src/constants.ts

@@ -0,0 +1,97 @@
+/**
+ * The binding powers for the various tokens in the JMESPath grammar.
+ *
+ * The binding powers are used to determine the order of operations for
+ * the parser. The higher the binding power, the more tightly the token
+ * binds to its arguments.
+ */
+const BINDING_POWER = {
+  eof: 0,
+  unquoted_identifier: 0,
+  quoted_identifier: 0,
+  literal: 0,
+  rbracket: 0,
+  rparen: 0,
+  comma: 0,
+  rbrace: 0,
+  number: 0,
+  current: 0,
+  expref: 0,
+  colon: 0,
+  pipe: 1,
+  or: 2,
+  and: 3,
+  eq: 5,
+  gt: 5,
+  lt: 5,
+  gte: 5,
+  lte: 5,
+  ne: 5,
+  flatten: 9,
+  // Everything above stops a projection.
+  star: 20,
+  filter: 21,
+  dot: 40,
+  not: 45,
+  lbrace: 50,
+  lbracket: 55,
+  lparen: 60,
+} as const;
+
+/**
+ * The set of ASCII lowercase letters allowed in JMESPath identifiers.
+ */
+const ASCII_LOWERCASE = 'abcdefghijklmnopqrstuvwxyz';
+/**
+ * The set of ASCII uppercase letters allowed in JMESPath identifiers.
+ */
+const ASCII_UPPERCASE = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
+/**
+ * The set of ASCII letters allowed in JMESPath identifiers.
+ */
+const ASCII_LETTERS = ASCII_LOWERCASE + ASCII_UPPERCASE;
+/**
+ * The set of ASCII digits allowed in JMESPath identifiers.
+ */
+const DIGITS = '0123456789';
+/**
+ * The set of ASCII letters and digits allowed in JMESPath identifiers.
+ */
+const START_IDENTIFIER = new Set(ASCII_LETTERS + '_');
+/**
+ * The set of ASCII letters and digits allowed in JMESPath identifiers.
+ */
+const VALID_IDENTIFIER = new Set(ASCII_LETTERS + DIGITS + '_');
+/**
+ * The set of ASCII digits allowed in JMESPath identifiers.
+ */
+const VALID_NUMBER = new Set(DIGITS);
+/**
+ * The set of ASCII whitespace characters allowed in JMESPath identifiers.
+ */
+const WHITESPACE = new Set(' \t\n\r');
+/**
+ * The set of simple tokens in the JMESPath grammar.
+ */
+const SIMPLE_TOKENS: Map<string, keyof typeof BINDING_POWER> = new Map([
+  ['.', 'dot'],
+  ['*', 'star'],
+  [':', 'colon'],
+  [']', 'rbracket'],
+  [',', 'comma'],
+  [':', 'colon'],
+  ['@', 'current'],
+  ['(', 'lparen'],
+  [')', 'rparen'],
+  ['{', 'lbrace'],
+  ['}', 'rbrace'],
+]);
+
+export {
+  BINDING_POWER,
+  SIMPLE_TOKENS,
+  START_IDENTIFIER,
+  VALID_IDENTIFIER,
+  VALID_NUMBER,
+  WHITESPACE,
+};