Statements

Statement blocks are blocks without output connections. These act like statements in text-based languages.

Just like all blocks in Blockly, statement blocks can be turned into code strings by defining a block-code generator.

import {javascriptGenerator} from 'blockly/javascript';

javascriptGenerator.forBlock['custom_block'] = function(block, generator) {
  // Collect argument strings.
  const fieldValue = block.getFieldValue('MY_FIELD');
  const innerCode = generator.statementToCode(block, 'MY_STATEMENT_INPUT');

  // Return code.
  return 'my code string';
}

Collect argument strings

All block-code generators require collecting the values of fields and collecting the code of inner blocks.

// Collect field values.
const fieldValue = block.getFieldValue('MY_FIELD');

// Collect inner block code strings.
const innerCode = generator.statementToCode(block, 'MY_STATEMENT_INPUT');

If you reference the code of an inner block multiple times, you should add argument caching to your block.

Return values

The return type of a statement block-code generator is a code string.

return 'my code string';