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# Logging
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Formatted logging system with consistent branding and error handling for CLI applications. Provides standardized output formatting with color-coded messages and NX branding.
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## Capabilities
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### Logger Object
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Main logging utility with methods for different message types and consistent formatting.
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```typescript { .api }
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/**
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 * Main logging utility object with formatted output methods
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 */
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export const logger: {
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  /** Logs warning messages in yellow */
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  warn(s: string | any): void;
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  /** Logs error messages in red, handles NX-prefixed messages and Error objects with stack traces */
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  error(s: string | Error | any): void;
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  /** Logs info messages with NX branding */
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  info(s: string | any): void;
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  /** Basic console.log wrapper */
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  log(...s: any[]): void;
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  /** Console debug wrapper */
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  debug(...s: any[]): void;
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  /** Console error wrapper for fatal errors */
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  fatal(...s: any[]): void;
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};
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```
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**Usage Examples:**
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```typescript
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import { logger } from "@nrwl/tao/shared/logger";
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// Basic logging
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logger.info("Starting workspace operation");
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logger.warn("Configuration file not found, using defaults");
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logger.error("Failed to read project configuration");
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// Error object handling
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try {
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  // some operation
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} catch (error) {
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  logger.error(error); // Automatically handles stack traces
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}
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// Debug information
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logger.debug("Processing file:", filePath);
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// Fatal errors
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logger.fatal("Critical error: workspace corrupted");
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```
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### Formatting Constants
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Pre-formatted branding constants for consistent message styling.
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```typescript { .api }
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/** Formatted prefix string with cyan "NX" branding */
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export const NX_PREFIX: string;
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/** Formatted error prefix string with red "ERROR" branding */
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export const NX_ERROR: string;
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```
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**Usage Examples:**
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```typescript
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import { NX_PREFIX, NX_ERROR } from "@nrwl/tao/shared/logger";
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console.log(`${NX_PREFIX} Custom operation completed`);
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console.log(`${NX_ERROR} Custom error occurred`);
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```
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### String Utilities
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Utility functions for string formatting and processing.
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```typescript { .api }
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/**
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 * Removes common leading whitespace from multi-line strings
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 * @param str - Multi-line string with potential indentation
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 * @returns String with common leading whitespace removed
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 */
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export function stripIndent(str: string): string;
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```
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**Usage Examples:**
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```typescript
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import { stripIndent } from "@nrwl/tao/shared/logger";
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const template = stripIndent`
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  This is a multi-line string
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    with various indentation levels
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      that will be normalized
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`;
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console.log(template);
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// Output:
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// This is a multi-line string
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//   with various indentation levels
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//     that will be normalized
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```
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## Integration Patterns
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The logging utilities integrate seamlessly with Nx operations:
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```typescript
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import { logger } from "@nrwl/tao/shared/logger";
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import { Workspaces } from "@nrwl/tao/shared/workspace";
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function processWorkspace(root: string) {
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  logger.info("Analyzing workspace structure");
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  try {
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    const workspaces = new Workspaces(root);
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    const projects = workspaces.readProjectsConfigurations();
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    logger.info(`Found ${Object.keys(projects.projects).length} projects`);
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  } catch (error) {
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    logger.error("Failed to read workspace configuration");
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    logger.error(error);
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  }
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}
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```