An experienced programmer shares a weekend project that builds a simplified BASIC variant, toybasic, and a three‑stage compiler written in Go—using Nex for lexical analysis, goyacc for parsing, and custom code generation—to translate BASIC programs into Go code, complete with examples and source links.
An in‑depth examination of a long‑standing PHP bug where the expression 0x00+2 incorrectly evaluates to 4, tracing its origin to the switch from flex to re2c in the lexer of PHP 5.3, detailing affected versions, code behavior, and the eventual fix in PHP 5.3.11.
This article guides readers through designing and implementing a basic Python interpreter that can evaluate arithmetic expressions by defining tokens, writing a lexer and parser with PLY, specifying BNF grammar, handling precedence, and assembling a runnable program that processes user input.
This article explains how to create a simple arithmetic expression interpreter in Python by leveraging the PLY (Python Lex‑Yacc) library, covering token definition, lexer implementation, BNF grammar, parser rules, operator precedence, error handling, and a complete runnable example.
This article explains the fundamentals of SQL parsing, covering lexer and parser mechanisms, context‑free grammar concepts, LL(1) and LR(1) parsing techniques, and demonstrates how Apache ShardingSphere implements a flexible, multi‑dialect SQL parser with features such as formatting, parameterization, and extensibility.
This article explains the fundamentals of SQL parsing, describing the roles of lexical analysis, syntax analysis, and visitors, and demonstrates the process with a concrete SELECT statement example, while also mentioning popular parsing libraries such as Druid and ANTLR.
This tutorial walks through constructing a JavaScript arithmetic parser using a finite‑state lexer, a stack‑based parser that builds an abstract syntax tree (AST), and an evaluator that supports numbers, operators, parentheses, vectors, and custom symbols like @rot and @dot, complete with visual demos.
This article explains the fundamentals of SQL parsing, compares popular parsers, details how ANTLR defines lexical and syntactic rules for SQL, and shows how Sharding‑Sphere leverages custom and ANTLR‑based parsers to extract sharding‑relevant context while balancing performance and compatibility.
