Tcl — Tutorials · VLSI Mentor

258Total chapters

30Modules

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30 / 30Active modules

Two parts, one dependency chain

Part I is a complete Tcl education that stands on its own — the execution model, expr, strings, lists, dicts and arrays, procedures, scope, files, regex and the error model — with no EDA tool and no VLSI knowledge assumed. Part II builds on it and never re-teaches it.

Standard Tcl, kept separate from tool commands

get_cells, create_clock and report_timing are taught as commands a vendor adds to its own interpreter, not as Tcl — named as such before any of them appears, with the portability limits stated rather than implied.

Script → constrain → sign-off

From the Tcl-as-command mental model to SDC constraint generators, multi-corner STA drivers, violation extractors, and PD report collectors — the full Tcl engineering loop every synthesis / STA / PD engineer owns.

Tcl Complete Curriculum

Your Learning Roadmap

258 chapters · 30 modules — two parts — Tcl taught from zero, then the Tcl a synthesis, STA, physical-design or verification engineer uses inside an EDA tool.

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Part I — Tcl Basics & Fundamentals

Tcl taught from zero with no EDA tool and no VLSI knowledge required: running your first script, the command-and-substitution execution model that explains everything else, values and expr, operators, strings, lists, dictionaries and arrays, conditions, iteration, procedures, scope and namespaces, files and paths, regular expressions, the error model, and assembling a script someone else can run.

Module 1

Introduction to Tcl

1.1What Tcl Is, and What It Was Built For 1.2Programming vs Scripting 1.3Where Tcl Runs: Standalone and Embedded 1.4tclsh: Finding and Checking the Interpreter 1.5The Interactive Prompt vs a .tcl File 1.6Writing and Running Your First Script 1.7puts: Making a Script Say Something 1.8Comments, and the One Place Tcl Allows Them 1.9When Tcl Refuses to Run: Reading the Error

Module 2

The Tcl Execution Model

2.1Everything Is a Command: command + words 2.2How Tcl Parses One Command 2.3Words and Whitespace: Where One Argument Ends 2.4Variable Substitution: $name 2.5Command Substitution: [ ... ]2.6Backslash Substitution and Escaping 2.7Double Quotes: Grouping With Substitution 2.8Braces: Grouping Without Substitution 2.9Braces vs Quotes: The Decision Rule 2.10Newlines, Semicolons, and Command Boundaries 2.11Substitution Happens Once — and Why eval Exists

Module 3

Values, Variables, and Expressions

3.1Everything Is a String 3.2set and $var: Creating and Reading a Variable 3.3Variable Names, and What Tcl Allows 3.4unset, and Testing Whether a Variable Exists 3.5Numbers: How Tcl Decides Something Is Numeric 3.6Truth in Tcl: What Counts as True and False 3.7expr: Arithmetic Is a Command, Not Syntax 3.8Why expr Arguments Belong in Braces 3.9incr: Counting Without expr 3.10Integer and Floating-Point Division 3.11Turning Text Into a Number You Can Trust

Module 4

Operators and Expressions

4.1Arithmetic Operators 4.2Precedence, Parentheses, and Readability 4.3Numeric Comparison, and the == Trap 4.4eq and ne: Comparing Strings on Purpose 4.5Logical Operators and Short-Circuit Evaluation 4.6Bitwise Operators 4.7The Conditional Operator 4.8Math Functions Inside expr 4.9in and ni: Membership Inside an Expression 4.10Floating-Point Equality and Precision

Module 5

Strings

5.1The string Command and Its Subcommands 5.2string length, and What a Character Is 5.3Indexing and Ranges: string index and string range 5.4Finding Text: string first and string last 5.5Glob Matching: string match 5.6Comparing Strings: string equal and string compare 5.7Case Conversion 5.8Trimming Whitespace 5.9Replacing and Mapping: string replace and string map 5.10append: Building a String Piece by Piece 5.11format: Producing Output You Can Line Up 5.12scan: Reading Fields Out of a Fixed Line 5.13split and join: The Bridge Between Strings and Lists

Module 6

Lists

6.1What a Tcl List Actually Is 6.2Building a List: list vs Writing Braces by Hand 6.3llength: How Many Elements 6.4lindex, and Counting From the End 6.5lrange: Taking a Slice 6.6lappend: Growing a List 6.7linsert and lreplace 6.8lset: Changing One Element in Place 6.9lsearch: Finding an Element 6.10lsort: Sorting by the Right Key 6.11Nested Lists 6.12concat vs list: The Flattening Difference 6.13{*} — Expanding a List Into Arguments 6.14lassign: Unpacking a List Into Variables

Module 7

Dictionaries and Arrays

7.1Two Ways to Hold Key-Value Data 7.2Dictionaries: dict set and dict get 7.3dict exists: Asking Before Reading 7.4dict keys, dict values, dict size 7.5dict for: Iterating Key and Value Together 7.6Nested Dictionaries 7.7dict with and dict update 7.8Arrays: Tcl's Original Associative Structure 7.9Reading and Writing Array Elements 7.10Inspecting an Array: array names, exists, size, parray 7.11Arrays vs Dictionaries: Choosing One 7.12Converting Between Arrays and Dictionaries

Module 8

Conditions and Control Flow

8.1if, elseif, else 8.2Why the Condition and the Body Both Need Braces 8.3Nested Conditions, and When to Flatten Them 8.4switch: Multi-Way Branching 8.5switch Matching Modes: -exact, -glob, -regexp 8.6Fallthrough and the default Branch 8.7Testing for a Value That Is Missing

Module 9

Loops and Iteration

9.1foreach: Iterating Over a List 9.2foreach Over Several Lists at Once 9.3foreach With Several Variables per Pass 9.4for: Index-Driven Loops 9.5while: Looping Until Something Changes 9.6break and continue 9.7Loop Bodies Need Braces: The Infinite-Loop Trap 9.8lmap: Building a List While You Iterate 9.9Accumulating Results Across an Iteration 9.10Nested Loops, and Keeping Them Readable

Module 10

Procedures and Reuse

10.1proc: Defining Your Own Command 10.2Arguments, and What Happens When the Count Is Wrong 10.3Default Arguments 10.4args: Taking Any Number of Arguments 10.5return, and the Value a Procedure Produces 10.6Local Variables: What a Procedure Can See 10.7Guard Clauses and Early Return 10.8Returning Lists and Dictionaries 10.9rename: Replacing or Wrapping an Existing Command 10.10When Something Deserves to Be a Procedure

Module 11

Scope and Namespaces

11.1Tcl's Scope Rules: Global and Local 11.2global: Reaching the Top-Level Scope 11.3Why Globals Make a Script Hard to Trust 11.4upvar: Operating on the Caller's Variable 11.5uplevel: Running a Script in Another Scope 11.6namespace eval: Giving Names a Home 11.7variable: State That Belongs to a Namespace 11.8Qualified Names and How Tcl Resolves Them 11.9Scope Bugs and How to Spot Them

Module 12

Files, Directories, and Paths

12.1Channels: How Tcl Talks to a File 12.2Reading a File Line by Line 12.3read: Taking the Whole File at Once 12.4Writing a File 12.5Append Mode, and Why the Mode Matters 12.6flush and close: Why Output Can Go Missing 12.7eof and the End of a Stream 12.8When the File Is Not There 12.9The file Command: exists, readable, size, mtime, type 12.10Paths: dirname, tail, rootname, extension, join 12.11file normalize, and Paths That Survive 12.12glob: Listing Files by Pattern 12.13Directories: mkdir, cd, pwd, delete

Module 13

Regular Expressions

13.1When a Regex Is the Right Tool, and When It Is Not 13.2regexp: Matching a Pattern 13.3Pattern Syntax: Classes, Anchors, Quantifiers 13.4Capture Groups, and Reading Them Out 13.5Why a Regex Belongs in Braces 13.6The Useful Switches: -all, -inline, -line, -nocase 13.7regsub: Substituting by Pattern 13.8Greedy and Non-Greedy Matching 13.9Regexes That Fail Silently 13.10Choosing Between string match and regexp

Module 14

Errors and Debugging

14.1Tcl's Error Model 14.2error: Raising Your Own 14.3catch: Handling an Error Without Stopping 14.4Return Codes: What catch Actually Reports 14.5try and finally 14.6The Message, errorInfo, and the Stack Trace 14.7The Three Errors You Will Actually Hit 14.8Quoting and Substitution Bugs 14.9puts Debugging, and parray 14.10Asking Tcl What It Knows: the info Commands 14.11Validating Input and Failing Loudly 14.12trace: Watching a Variable or Command

Module 15

Building Tcl Programs

15.1source: Running One Script From Another 15.2argv, argc and argv0: Command-Line Arguments 15.3Parsing Options From argv 15.4exit, and the Status the Caller Sees 15.5The env Array: Reading the Environment 15.6exec: Running Another Program 15.7Splitting a Script Into Reusable Files 15.8package require and package provide 15.9A Layout That Survives Being Inherited

Part II — Tcl for VLSI & EDA Engineering

The Part I foundation applied to semiconductor work, and never re-teaching it: how a tool embeds Tcl and where vendors diverge, collections and design objects, querying a design database, SDC as Tcl, synthesis and STA automation, physical design, simulator and verification Tcl, report and log processing, multi-corner multi-mode flows, reusable flow infrastructure, the hand-off to Bash / Make / Python, debugging a production flow, and the scripts engineers actually ship.

Module 16

Why Tcl Matters in VLSI

16.1Why EDA Tools Embed Tcl 16.2Tcl Across the Semiconductor Flow 16.3Tcl, Bash and Python: Which Does What 16.4Standard Tcl vs Tool Commands: The Boundary

Module 17

Understanding EDA Tcl Environments