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App.svelte
<script>
let agility = 0;
let power = 0;
function incrementAgility() {
agility ++;
}
function incrementPower() {
power ++;
}
function levelUp() {
agility += 5;
power += 7;
}
</script>

Agility: {agility}
Power: {power}
Stats: {agility * power}

<button on:click={incrementAgility}>+ Agility</button>
<button on:click={incrementPower}>+ Power</button>
<button on:click={levelUp}>Level Up</button>
fetching https://unpkg.com/svelte@5.20.5/src/internal/client/index.js
import 'svelte/internal/disclose-version';
import 'svelte/internal/flags/legacy';
import * as $ from 'svelte/internal/client';

var root = $.template(` <button>+ Agility</button> <button>+ Power</button> <button>Level Up</button>`, 1);

export default function App($$anchor) {
let agility = $.mutable_state(0);
let power = $.mutable_state(0);

function incrementAgility() {
$.update(agility);
}

function incrementPower() {
$.update(power);
}

function levelUp() {
$.set(agility, $.get(agility) + 5);
$.set(power, $.get(power) + 7);
}

$.next();

var fragment = root();
var text = $.first_child(fragment);
var button = $.sibling(text);
var button_1 = $.sibling(button, 2);
var button_2 = $.sibling(button_1, 2);

$.template_effect(() => $.set_text(text, `Agility: ${$.get(agility) ?? ''}
Power: ${$.get(power) ?? ''}
Stats: ${$.get(agility) * $.get(power)} `));

$.event('click', button, incrementAgility);
result = svelte.compile(source, {
generate: ,
});
/* Add a <style> tag to see the CSS output */
		
			
				
  • Root {
    • css: null
    • js: []
    • start: 217
    • end: 427
    • type: "Root"
    • fragment: Fragment {...}
      • type: "Fragment"
      • nodes: [...] (12)
        • Text {...}
          • type: "Text"
          • start: 215
          • end: 226
          • raw: "Agility: "
          • data: "Agility: "
          }
        • ExpressionTag {...}
          • type: "ExpressionTag"
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          • end: 235
          • expression: Identifier {...}
            • type: "Identifier"
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            • loc: {...}
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                • column: 10
                }
              • end: {...}
                • line: 16
                • column: 17
                }
              }
            • name: "agility"
            }
          }
        • Text {...}
          • type: "Text"
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          • end: 243
          • raw: "\nPower: "
          • data: "\nPower: "
          }
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          • type: "ExpressionTag"
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          • end: 250
          • expression: Identifier {...}
            • type: "Identifier"
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            • loc: {...}
              • start: {...}
                • line: 17
                • column: 8
                }
              • end: {...}
                • line: 17
                • column: 13
                }
              }
            • name: "power"
            }
          }
        • Text {...}
          • type: "Text"
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          • end: 258
          • raw: "\nStats: "
          • data: "\nStats: "
          }
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          • end: 275
          • expression: BinaryExpression {...}
            • type: "BinaryExpression"
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            • loc: {...}
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                }
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                • column: 23
                }
              }
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              • loc: {...}
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                  • column: 15
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                }
              • name: "agility"
              }
            • operator: "*"
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              • loc: {...}
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                  • column: 18
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                • end: {...}
                  • line: 18
                  • column: 23
                  }
                }
              • name: "power"
              }
            }
          }
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          • raw: " "
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          }
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          • name: "button"
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                    • column: 34
                    }
                  }
                • name: "incrementAgility"
                }
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              }
            ]
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              • Text {...}
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                • raw: "+ Agility"
                • data: "+ Agility"
                }
              ]
            }
          }
        • Text {...}
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          • raw: " "
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          }
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          • name: "button"
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              • type: "OnDirective"
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                  }
                • name: "incrementPower"
                }
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              }
            ]
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            • type: "Fragment"
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                • raw: "+ Power"
                • data: "+ Power"
                }
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                • loc: {...}
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                    }
                  • end: {...}
                    • line: 22
                    • column: 25
                    }
                  }
                • name: "levelUp"
                }
              • modifiers: []
              }
            ]
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            • type: "Fragment"
            • nodes: [...] (1)
              • Text {...}
                • type: "Text"
                • start: 410
                • end: 418
                • raw: "Level Up"
                • data: "Level Up"
                }
              ]
            }
          }
        ]
      }
    • options: null
    • instance: Script {...}
      • type: "Script"
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      • context: "default"
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                  }
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              • end: 144
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                      }
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                      }
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                      • raw: "7"
                      }
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              }
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          ]
        • sourceType: "module"
        }
      • attributes: []
      }
    }
The AST is not public API and may change at any point in time
Compile Svelte in your Head - Reactivity • Playground • Svelte