The Pollyanna/Playing With

Basic Trope: A character is irrepressibly sweet-natured and optimistic, whatever comes their way.
 * Straight: Polly is unappreciated at work and taken for granted by her husband, but she always seems to look on the bright side.
 * Exaggerated: Purity Sue
 * Downplayed: Polly is more optimistic than average, but has a breaking point.
 * Justified: Polly is a Fisher King, and knows that her getting into a bad mood will only make the world worse.
 * Polly is The Fundamentalist, and believes that whatever befalls her on Earth will be compensated a thousandfold in the afterlife.
 * Inverted: The Eeyore
 * Subverted: Polly is revealed to be a Stepford Smiler.
 * Beware the Nice Ones - she might seem lovey-dovey, but she can kick ass if she needs too.
 * Double Subverted: Polly's cheery facade may have cracked, but her optimism is sincerely felt - everyone has their off days.
 * Parodied: Polly skips, smiling, through a Crapsack World, singing duets with turkey vultures and blowing kisses to Disaster Scavengers.
 * Zig Zagged: The work veers all over the Sliding Scale of Idealism Versus Cynicism, while Polly's characterisation switches from Princess Classic to Stepford Smiler Depending On the Writer.
 * Averted: Polly's fairly realistic in her worldview.
 * Deconstructed: Polly's sunny outlook doesn't stop the world trying its best to Break the Cutie. It's revealed to be a struggle for her to constantly pretend to be in a good mood, putting her under even more stress than simply riding out the storm would have done.
 * Reconstructed: Maybe the world isn't perfect. Maybe all isn't for the best in the best of all possible worlds. But Polly sees no point in despairing or giving in to cynicism, and honestly finds comfort in looking on the bright side of whatever happens.
 * Enforced: "This is a kids show, but we've made it into a bit of a Crap Saccharine World. We need the hero to look on the bright side or the kids might start noticing the Nightmare Fuel"
 * Lampshaded: "Do you ever stop smiling?"
 * Invoked: Polly believes in karma - if she's nice to everyone else, they're more likely to be nice to her.
 * Exploited: ???
 * Defied: "Just because I'm the Token Girl doesn't mean I'm going to keep all your spirits up! This place sucks!"
 * Discussed: "Why couldn't my sidekick be one of those irrepressible happy little girl sidekicks? I'm sick of this Deadpan Snarker following me around"
 * Conversed: ???

Wasn't that fun? And this one little link will take you straight back to The Pollyanna. Yay!