Understanding Case Handling in MBASIC¶

What is "Case Handling"?¶

MBASIC, like all classic BASIC interpreters, is case-insensitive. This means:

10 MyVariable = 5
20 myvariable = 10
30 MYVARIABLE = 15

All three lines refer to the same variable. The value is now 15.

But here's the new question: Which spelling should MBASIC show you? Should it be MyVariable, myvariable, or MYVARIABLE?

This is what "case handling" controls.

Why Does This Matter?¶

Problem 1: Accidental Typos¶

Imagine you're writing a program:

10 TotalCount = 0
20 FOR I = 1 TO 10
30   TotalCont = TotalCount + I   ← Typo! Missing 'u' in TotalCount
40 NEXT I
50 PRINT TotalCount

What happens? - Without case conflict detection: Prints 0 (the loop creates a new variable TotalCont but never updates TotalCount!) - With case conflict detection: Error at line 30 - catches the typo immediately

This is a real bug that's hard to spot. Case handling can catch it.

Problem 2: Inconsistent Style¶

When copying code from different sources:

10 REM From Program A
20 PlayerScore = 100
30 REM From Program B
40 playerscore = 200

Is this one variable or two? (It's one!) But it looks confusing.

Problem 3: Team Projects¶

When multiple people work on the same program, everyone may have different habits:

REM Person A likes: TargetAngle
REM Person B likes: targetangle
REM Person C likes: TARGETANGLE

Without case handling, the same variable appears three different ways in your code!

How MBASIC Solves This¶

MBASIC gives you two separate case handling systems:

Variable Case Handling - Controls how variable names are displayed
Keyword Case Handling - Controls how keywords like PRINT, FOR, IF are displayed

You can configure each independently!

Variable Case Handling¶

Setting: `variables.case_conflict`¶

Controls what MBASIC does when the same variable appears with different cases.

Option 1: `first_wins` (Default)¶

What it does: The first spelling you use becomes the official spelling.

10 TargetAngle = 45
20 targetangle = 90  ← MBASIC uses "TargetAngle" everywhere
30 PRINT TargetAngle  ← Displays "TargetAngle = 90"

When to use: - Solo projects - When you want freedom to type casually - You're consistent naturally

Pros: Flexible, doesn't interrupt your work Cons: Won't catch typos

Option 2: `error`¶

What it does: Shows an error if you spell the same variable differently.

10 TotalCount = 0
20 TotalCont = TotalCont + 5  ← ERROR!

Error message:

Variable name case conflict: 'TotalCont' at line 20 vs 'TotalCount' at line 10

When to use: - Team projects - When you want to catch typos - Professional/shared code

Pros: Catches bugs immediately Cons: Requires fixing before running

Option 3: `prefer_upper`¶

What it does: Always uses the version with MOST CAPITAL LETTERS.

10 targetangle = 45   ← 0 capital letters
20 TargetAngle = 90   ← 2 capital letters
30 TARGETANGLE = 100  ← 11 capital letters (winner!)

MBASIC shows: TARGETANGLE = 100 everywhere

When to use: - Classic BASIC style (retro computing) - Want that vintage look

Option 4: `prefer_lower`¶

What it does: Always uses the version with most lowercase letters.

10 COUNTER = 10  ← 7 capital letters
20 counter = 20  ← 7 lowercase letters (winner!)

MBASIC shows: counter = 20

When to use: - Modern style (like Python) - Easier to read for long sessions

Option 5: `prefer_mixed`¶

What it does: Prefers camelCase or PascalCase style.

10 targetangle = 10   ← All lowercase
20 TARGETANGLE = 20   ← All uppercase
30 TargetAngle = 30   ← Mixed case (winner!)

MBASIC shows: TargetAngle = 30

When to use: - Modern readable code - Professional appearance - Mixed with other languages

Keyword Case Handling¶

Setting: `keywords.case_style`¶

Controls how keywords (PRINT, FOR, IF, END, etc.) are displayed.

Option 1: `force_lower` (Default)¶

What it does: All keywords shown in lowercase.

You type:    10 PRINT "hello"
             20 Print "world"
             30 print "!"

MBASIC shows: 10 print "hello"
              20 print "world"
              30 print "!"

When to use: - Default MBASIC 5.21 style - Matches original behavior

Option 2: `force_upper`¶

What it does: All keywords shown in UPPERCASE.

You type:    10 print "hello"
             20 Print "world"

MBASIC shows: 10 PRINT "hello"
              20 PRINT "world"

When to use: - Classic BASIC appearance - Vintage computing feel - Visually distinct from variables

Option 3: `force_capitalize` ⭐ Popular!¶

What it does: Keywords shown as Capitalized (first letter uppercase).

You type:    10 PRINT "hello"
             20 for i = 1 to 10
             30 IF x = 5 THEN GOTO 100

MBASIC shows: 10 Print "hello"
              20 For i = 1 To 10
              30 If x = 5 Then Goto 100

When to use: - Modern readable style - Teaching/tutorials - Professional documentation - Easier on the eyes than ALL CAPS

Why it's popular: - More readable than PRINT or print - Looks professional - Similar to modern languages - Clear but not shouty

Option 4: `first_wins`¶

What it does: First spelling of each keyword becomes official.

You type:    10 Print "hello"
             20 PRINT "world"

MBASIC shows: 10 Print "hello"
              20 Print "world"  ← Uses first spelling

When to use: - You have a preferred style and stick to it - Importing code from different sources

Option 5: `error`¶

What it does: Error if same keyword spelled differently.

10 Print "hello"
20 PRINT "world"  ← ERROR: Keyword case conflict!

When to use: - Enforcing strict style guidelines - Team projects with coding standards

Option 6: `preserve`¶

What it does: Every keyword stays exactly as you typed it.

You type:    10 PRINT "hello"
             20 print "world"
             30 Print "!"

MBASIC shows: 10 PRINT "hello"
              20 print "world"
              30 Print "!"

When to use: - Maximum flexibility - Artistic code formatting - Special presentations

Common Scenarios¶

Scenario 1: Solo Hobbyist¶

You want: Freedom to code casually, no interruptions

Settings:

SET "variables.case_conflict" "first_wins"
SET "keywords.case_style" "force_lower"

Result: Type naturally, MBASIC handles everything silently.

Scenario 2: Teaching/Tutorials¶

You want: Clear, readable code for students

Settings:

SET "variables.case_conflict" "prefer_mixed"
SET "keywords.case_style" "force_capitalize"

Result:

10 For Count = 1 To 10
20   Print "Number:"; Count
30 Next Count

Professional and easy to read!

Scenario 3: Team Project¶

You want: Catch mistakes, enforce consistency

Settings:

SET "variables.case_conflict" "error"
SET "keywords.case_style" "force_capitalize"

Result: Any inconsistency is flagged immediately. Forces team to agree on style.

Scenario 4: Retro/Vintage Look¶

You want: Classic BASIC appearance

Settings:

SET "variables.case_conflict" "prefer_upper"
SET "keywords.case_style" "force_upper"

Result:

10 FOR COUNT = 1 TO 10
20   PRINT "NUMBER:"; COUNT
30 NEXT COUNT

Looks like it came from a 1970s terminal!

Scenario 5: Modern Python-like Style¶

You want: Contemporary programming feel

Settings:

SET "variables.case_conflict" "prefer_lower"
SET "keywords.case_style" "force_capitalize"

Result:

10 For counter = 1 To 10
20   Print "value:"; counter
30 Next counter

Familiar to modern programmers!

How to Change Settings¶

View Current Settings¶

SHOW SETTINGS

Shows all settings and their values.

View Specific Category¶

SHOW SETTINGS "variables"
SHOW SETTINGS "keywords"

Change a Setting¶

SET "variables.case_conflict" "error"
SET "keywords.case_style" "force_capitalize"

Get Help on a Setting¶

HELP SET "variables.case_conflict"
HELP SET "keywords.case_style"

Shows detailed explanation and examples.

Configuration Files¶

Settings can be saved to files for persistence:

Global Settings (All Projects)¶

File: ~/.mbasic/settings.json

{
  "variables.case_conflict": "first_wins",
  "keywords.case_style": "force_lower"
}

Project Settings (This Project Only)¶

File: .mbasic/settings.json (in your project directory)

{
  "variables.case_conflict": "error",
  "keywords.case_style": "force_capitalize"
}

Project settings override global settings.

Debugging Case Issues¶

Problem: "Why does my variable look different than I typed?"¶

Answer: Check your variables.case_conflict setting.

SHOW SETTINGS "variables.case_conflict"

If it's first_wins, the first spelling is used everywhere.

Problem: "I want to find all case variations of a variable"¶

Answer: Use the error policy temporarily:

SET "variables.case_conflict" "error"
RUN

MBASIC will show you exactly where different cases appear.

Then fix them or change back to your preferred policy.

Problem: "Keywords look weird after editing"¶

Answer: Check your keywords.case_style:

SHOW SETTINGS "keywords.case_style"

Change it to your preference:

SET "keywords.case_style" "force_capitalize"

Best Practices¶

For Personal Projects¶

Use first_wins for variables (freedom)
Use force_capitalize for keywords (readability)
Be consistent within each program

For Team Projects¶

Use error for variables (catch mistakes)
Agree on keyword style (document it)
Add settings to .mbasic/settings.json in project

For Published Code¶

Use consistent style throughout
Consider prefer_mixed for variables
Use force_capitalize for keywords
Test with error policy before publishing

For Teaching¶

Use force_capitalize for keywords
Use prefer_mixed for variables
Show students the settings
Explain why consistency matters

Technical Background¶

Why is BASIC Case-Insensitive?¶

Historical reasons: 1. 1960s-70s computers: Many terminals were uppercase-only 2. Simplicity: Easier for beginners (no remembering exact case) 3. Compatibility: Code works regardless of how typed

Why Add Case Handling Now?¶

Modern benefits: 1. Better error detection: Catch typos automatically 2. Code readability: Consistent style is easier to read 3. Team collaboration: Everyone sees same style 4. Educational: Teaches good programming habits

Comparison to Other Languages¶

Language	Case Sensitive?	Variable Display
Python	Yes	Exactly as typed
JavaScript	Yes	Exactly as typed
SQL	No	Varies by tool
BASIC	No	You choose!

MBASIC gives you the best of both worlds: - Case-insensitive (easy for beginners) - Configurable display (professional results)

Real-World Example¶

Here's a complete program showing the difference:

With Default Settings¶

10 REM Calculate average
20 Total = 0
30 FOR count = 1 TO 5
40   INPUT "Enter number"; num
50   total = total + num
60 NEXT count
70 Average = total / count
80 PRINT "Average is:"; average
90 END

Variables appear with mixed cases (first-seen). Hard to read.

With Recommended Settings¶

SET "variables.case_conflict" "prefer_mixed"
SET "keywords.case_style" "force_capitalize"

Result:

10 Rem Calculate average
20 Total = 0
30 For Count = 1 To 5
40   Input "Enter number"; Num
50   Total = Total + Num
60 Next Count
70 Average = Total / Count
80 Print "Average is:"; Average
90 End

Much more professional and readable!

Quick Reference Card¶

Most Popular Combinations¶

Beginner Friendly:

SET "variables.case_conflict" "first_wins"
SET "keywords.case_style" "force_capitalize"

Professional:

SET "variables.case_conflict" "prefer_mixed"
SET "keywords.case_style" "force_capitalize"

Strict/Team:

SET "variables.case_conflict" "error"
SET "keywords.case_style" "force_capitalize"

Vintage:

SET "variables.case_conflict" "prefer_upper"
SET "keywords.case_style" "force_upper"

Modern:

SET "variables.case_conflict" "prefer_lower"
SET "keywords.case_style" "force_capitalize"

Summary¶

Case handling is about making your code look the way you want while catching mistakes.

Key Points: 1. BASIC remains case-insensitive (that won't change) 2. You control how variables and keywords are displayed 3. Settings can catch typos and enforce style 4. Different settings for different situations 5. Configuration saved per-project or globally

Start Here:

SHOW SETTINGS
HELP SET "variables.case_conflict"
HELP SET "keywords.case_style"

Experiment until you find what works for you!

Understanding Case Handling in MBASIC¶

What is "Case Handling"?¶

Why Does This Matter?¶

Problem 1: Accidental Typos¶

Problem 2: Inconsistent Style¶

Problem 3: Team Projects¶

How MBASIC Solves This¶

Variable Case Handling¶

Setting: variables.case_conflict¶

Option 1: first_wins (Default)¶

Option 2: error¶

Option 3: prefer_upper¶

Option 4: prefer_lower¶

Option 5: prefer_mixed¶

Keyword Case Handling¶

Setting: keywords.case_style¶

Option 1: force_lower (Default)¶

Option 2: force_upper¶

Option 3: force_capitalize ⭐ Popular!¶

Option 4: first_wins¶

Option 5: error¶

Option 6: preserve¶

Common Scenarios¶

Scenario 1: Solo Hobbyist¶

Scenario 2: Teaching/Tutorials¶

Scenario 3: Team Project¶

Scenario 4: Retro/Vintage Look¶

Scenario 5: Modern Python-like Style¶

How to Change Settings¶

View Current Settings¶

View Specific Category¶

Change a Setting¶

Get Help on a Setting¶

Configuration Files¶

Global Settings (All Projects)¶

Project Settings (This Project Only)¶

Debugging Case Issues¶

Problem: "Why does my variable look different than I typed?"¶

Problem: "I want to find all case variations of a variable"¶

Problem: "Keywords look weird after editing"¶

Best Practices¶

For Personal Projects¶

For Team Projects¶

For Published Code¶

For Teaching¶

Technical Background¶

Why is BASIC Case-Insensitive?¶

Why Add Case Handling Now?¶

Comparison to Other Languages¶

Real-World Example¶

With Default Settings¶

With Recommended Settings¶

Quick Reference Card¶

Most Popular Combinations¶

Summary¶

See Also¶

Setting: `variables.case_conflict`¶

Option 1: `first_wins` (Default)¶

Option 2: `error`¶

Option 3: `prefer_upper`¶

Option 4: `prefer_lower`¶

Option 5: `prefer_mixed`¶

Setting: `keywords.case_style`¶

Option 1: `force_lower` (Default)¶

Option 2: `force_upper`¶

Option 3: `force_capitalize` ⭐ Popular!¶

Option 4: `first_wins`¶

Option 5: `error`¶

Option 6: `preserve`¶